radangel/html/js/chroma.js

/**
 * @license
 *
 * chroma.js - JavaScript library for color conversions
 * 
 * Copyright (c) 2011-2017, Gregor Aisch
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * 
 * 1. Redistributions of source code must retain the above copyright notice, this
 *    list of conditions and the following disclaimer.
 * 
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 * 
 * 3. The name Gregor Aisch may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL GREGOR AISCH OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

(function() {
  var Color, DEG2RAD, LAB_CONSTANTS, PI, PITHIRD, RAD2DEG, TWOPI, _average_lrgb, _guess_formats, _guess_formats_sorted, _input, _interpolators, abs, atan2, bezier, blend, blend_f, brewer, burn, chroma, clip_rgb, cmyk2rgb, colors, cos, css2rgb, darken, dodge, each, floor, hcg2rgb, hex2rgb, hsi2rgb, hsl2css, hsl2rgb, hsv2rgb, interpolate, interpolate_hsx, interpolate_lab, interpolate_lrgb, interpolate_num, interpolate_rgb, lab2lch, lab2rgb, lab_xyz, lch2lab, lch2rgb, lighten, limit, log, luminance_x, m, max, multiply, normal, num2rgb, overlay, pow, rgb2cmyk, rgb2css, rgb2hcg, rgb2hex, rgb2hsi, rgb2hsl, rgb2hsv, rgb2lab, rgb2lch, rgb2luminance, rgb2num, rgb2temperature, rgb2xyz, rgb_xyz, rnd, root, round, screen, sin, sqrt, temperature2rgb, type, unpack, w3cx11, xyz_lab, xyz_rgb,
    slice = [].slice;

  type = (function() {

    /*
    for browser-safe type checking+
    ported from jQuery's $.type
     */
    var classToType, len, name, o, ref;
    classToType = {};
    ref = "Boolean Number String Function Array Date RegExp Undefined Null".split(" ");
    for (o = 0, len = ref.length; o < len; o++) {
      name = ref[o];
      classToType["[object " + name + "]"] = name.toLowerCase();
    }
    return function(obj) {
      var strType;
      strType = Object.prototype.toString.call(obj);
      return classToType[strType] || "object";
    };
  })();

  limit = function(x, min, max) {
    if (min == null) {
      min = 0;
    }
    if (max == null) {
      max = 1;
    }
    if (x < min) {
      x = min;
    }
    if (x > max) {
      x = max;
    }
    return x;
  };

  unpack = function(args) {
    if (args.length >= 3) {
      return Array.prototype.slice.call(args);
    } else {
      return args[0];
    }
  };

  clip_rgb = function(rgb) {
    var i, o;
    rgb._clipped = false;
    rgb._unclipped = rgb.slice(0);
    for (i = o = 0; o < 3; i = ++o) {
      if (i < 3) {
        if (rgb[i] < 0 || rgb[i] > 255) {
          rgb._clipped = true;
        }
        if (rgb[i] < 0) {
          rgb[i] = 0;
        }
        if (rgb[i] > 255) {
          rgb[i] = 255;
        }
      } else if (i === 3) {
        if (rgb[i] < 0) {
          rgb[i] = 0;
        }
        if (rgb[i] > 1) {
          rgb[i] = 1;
        }
      }
    }
    if (!rgb._clipped) {
      delete rgb._unclipped;
    }
    return rgb;
  };

  PI = Math.PI, round = Math.round, cos = Math.cos, floor = Math.floor, pow = Math.pow, log = Math.log, sin = Math.sin, sqrt = Math.sqrt, atan2 = Math.atan2, max = Math.max, abs = Math.abs;

  TWOPI = PI * 2;

  PITHIRD = PI / 3;

  DEG2RAD = PI / 180;

  RAD2DEG = 180 / PI;

  chroma = function() {
    if (arguments[0] instanceof Color) {
      return arguments[0];
    }
    return (function(func, args, ctor) {
      ctor.prototype = func.prototype;
      var child = new ctor, result = func.apply(child, args);
      return Object(result) === result ? result : child;
    })(Color, arguments, function(){});
  };

  chroma["default"] = chroma;

  _interpolators = [];

  if ((typeof module !== "undefined" && module !== null) && (module.exports != null)) {
    module.exports = chroma;
  }

  if (typeof define === 'function' && define.amd) {
    define([], function() {
      return chroma;
    });
  } else {
    root = typeof exports !== "undefined" && exports !== null ? exports : this;
    root.chroma = chroma;
  }

  chroma.version = '1.4.0';

  _input = {};

  _guess_formats = [];

  _guess_formats_sorted = false;

  Color = (function() {
    function Color() {
      var arg, args, chk, len, len1, me, mode, o, w;
      me = this;
      args = [];
      for (o = 0, len = arguments.length; o < len; o++) {
        arg = arguments[o];
        if (arg != null) {
          args.push(arg);
        }
      }
      if (args.length > 1) {
        mode = args[args.length - 1];
      }
      if (_input[mode] != null) {
        me._rgb = clip_rgb(_input[mode](unpack(args.slice(0, -1))));
      } else {
        if (!_guess_formats_sorted) {
          _guess_formats = _guess_formats.sort(function(a, b) {
            return b.p - a.p;
          });
          _guess_formats_sorted = true;
        }
        for (w = 0, len1 = _guess_formats.length; w < len1; w++) {
          chk = _guess_formats[w];
          mode = chk.test.apply(chk, args);
          if (mode) {
            break;
          }
        }
        if (mode) {
          me._rgb = clip_rgb(_input[mode].apply(_input, args));
        }
      }
      if (me._rgb == null) {
        console.warn('unknown format: ' + args);
      }
      if (me._rgb == null) {
        me._rgb = [0, 0, 0];
      }
      if (me._rgb.length === 3) {
        me._rgb.push(1);
      }
    }

    Color.prototype.toString = function() {
      return this.hex();
    };

    return Color;

  })();

  chroma._input = _input;


  /**
  	ColorBrewer colors for chroma.js
  
  	Copyright (c) 2002 Cynthia Brewer, Mark Harrower, and The 
  	Pennsylvania State University.
  
  	Licensed under the Apache License, Version 2.0 (the "License"); 
  	you may not use this file except in compliance with the License.
  	You may obtain a copy of the License at	
  	http://www.apache.org/licenses/LICENSE-2.0
  
  	Unless required by applicable law or agreed to in writing, software distributed
  	under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
  	CONDITIONS OF ANY KIND, either express or implied. See the License for the
  	specific language governing permissions and limitations under the License.
  
      @preserve
   */

  chroma.brewer = brewer = {
    OrRd: ['#fff7ec', '#fee8c8', '#fdd49e', '#fdbb84', '#fc8d59', '#ef6548', '#d7301f', '#b30000', '#7f0000'],
    PuBu: ['#fff7fb', '#ece7f2', '#d0d1e6', '#a6bddb', '#74a9cf', '#3690c0', '#0570b0', '#045a8d', '#023858'],
    BuPu: ['#f7fcfd', '#e0ecf4', '#bfd3e6', '#9ebcda', '#8c96c6', '#8c6bb1', '#88419d', '#810f7c', '#4d004b'],
    Oranges: ['#fff5eb', '#fee6ce', '#fdd0a2', '#fdae6b', '#fd8d3c', '#f16913', '#d94801', '#a63603', '#7f2704'],
    BuGn: ['#f7fcfd', '#e5f5f9', '#ccece6', '#99d8c9', '#66c2a4', '#41ae76', '#238b45', '#006d2c', '#00441b'],
    YlOrBr: ['#ffffe5', '#fff7bc', '#fee391', '#fec44f', '#fe9929', '#ec7014', '#cc4c02', '#993404', '#662506'],
    YlGn: ['#ffffe5', '#f7fcb9', '#d9f0a3', '#addd8e', '#78c679', '#41ab5d', '#238443', '#006837', '#004529'],
    Reds: ['#fff5f0', '#fee0d2', '#fcbba1', '#fc9272', '#fb6a4a', '#ef3b2c', '#cb181d', '#a50f15', '#67000d'],
    RdPu: ['#fff7f3', '#fde0dd', '#fcc5c0', '#fa9fb5', '#f768a1', '#dd3497', '#ae017e', '#7a0177', '#49006a'],
    Greens: ['#f7fcf5', '#e5f5e0', '#c7e9c0', '#a1d99b', '#74c476', '#41ab5d', '#238b45', '#006d2c', '#00441b'],
    YlGnBu: ['#ffffd9', '#edf8b1', '#c7e9b4', '#7fcdbb', '#41b6c4', '#1d91c0', '#225ea8', '#253494', '#081d58'],
    Purples: ['#fcfbfd', '#efedf5', '#dadaeb', '#bcbddc', '#9e9ac8', '#807dba', '#6a51a3', '#54278f', '#3f007d'],
    GnBu: ['#f7fcf0', '#e0f3db', '#ccebc5', '#a8ddb5', '#7bccc4', '#4eb3d3', '#2b8cbe', '#0868ac', '#084081'],
    Greys: ['#ffffff', '#f0f0f0', '#d9d9d9', '#bdbdbd', '#969696', '#737373', '#525252', '#252525', '#000000'],
    YlOrRd: ['#ffffcc', '#ffeda0', '#fed976', '#feb24c', '#fd8d3c', '#fc4e2a', '#e31a1c', '#bd0026', '#800026'],
    PuRd: ['#f7f4f9', '#e7e1ef', '#d4b9da', '#c994c7', '#df65b0', '#e7298a', '#ce1256', '#980043', '#67001f'],
    Blues: ['#f7fbff', '#deebf7', '#c6dbef', '#9ecae1', '#6baed6', '#4292c6', '#2171b5', '#08519c', '#08306b'],
    PuBuGn: ['#fff7fb', '#ece2f0', '#d0d1e6', '#a6bddb', '#67a9cf', '#3690c0', '#02818a', '#016c59', '#014636'],
    Viridis: ['#440154', '#482777', '#3f4a8a', '#31678e', '#26838f', '#1f9d8a', '#6cce5a', '#b6de2b', '#fee825'],
    Spectral: ['#9e0142', '#d53e4f', '#f46d43', '#fdae61', '#fee08b', '#ffffbf', '#e6f598', '#abdda4', '#66c2a5', '#3288bd', '#5e4fa2'],
    RdYlGn: ['#a50026', '#d73027', '#f46d43', '#fdae61', '#fee08b', '#ffffbf', '#d9ef8b', '#a6d96a', '#66bd63', '#1a9850', '#006837'],
    RdBu: ['#67001f', '#b2182b', '#d6604d', '#f4a582', '#fddbc7', '#f7f7f7', '#d1e5f0', '#92c5de', '#4393c3', '#2166ac', '#053061'],
    PiYG: ['#8e0152', '#c51b7d', '#de77ae', '#f1b6da', '#fde0ef', '#f7f7f7', '#e6f5d0', '#b8e186', '#7fbc41', '#4d9221', '#276419'],
    PRGn: ['#40004b', '#762a83', '#9970ab', '#c2a5cf', '#e7d4e8', '#f7f7f7', '#d9f0d3', '#a6dba0', '#5aae61', '#1b7837', '#00441b'],
    RdYlBu: ['#a50026', '#d73027', '#f46d43', '#fdae61', '#fee090', '#ffffbf', '#e0f3f8', '#abd9e9', '#74add1', '#4575b4', '#313695'],
    BrBG: ['#543005', '#8c510a', '#bf812d', '#dfc27d', '#f6e8c3', '#f5f5f5', '#c7eae5', '#80cdc1', '#35978f', '#01665e', '#003c30'],
    RdGy: ['#67001f', '#b2182b', '#d6604d', '#f4a582', '#fddbc7', '#ffffff', '#e0e0e0', '#bababa', '#878787', '#4d4d4d', '#1a1a1a'],
    PuOr: ['#7f3b08', '#b35806', '#e08214', '#fdb863', '#fee0b6', '#f7f7f7', '#d8daeb', '#b2abd2', '#8073ac', '#542788', '#2d004b'],
    Set2: ['#66c2a5', '#fc8d62', '#8da0cb', '#e78ac3', '#a6d854', '#ffd92f', '#e5c494', '#b3b3b3'],
    Accent: ['#7fc97f', '#beaed4', '#fdc086', '#ffff99', '#386cb0', '#f0027f', '#bf5b17', '#666666'],
    Set1: ['#e41a1c', '#377eb8', '#4daf4a', '#984ea3', '#ff7f00', '#ffff33', '#a65628', '#f781bf', '#999999'],
    Set3: ['#8dd3c7', '#ffffb3', '#bebada', '#fb8072', '#80b1d3', '#fdb462', '#b3de69', '#fccde5', '#d9d9d9', '#bc80bd', '#ccebc5', '#ffed6f'],
    Dark2: ['#1b9e77', '#d95f02', '#7570b3', '#e7298a', '#66a61e', '#e6ab02', '#a6761d', '#666666'],
    Paired: ['#a6cee3', '#1f78b4', '#b2df8a', '#33a02c', '#fb9a99', '#e31a1c', '#fdbf6f', '#ff7f00', '#cab2d6', '#6a3d9a', '#ffff99', '#b15928'],
    Pastel2: ['#b3e2cd', '#fdcdac', '#cbd5e8', '#f4cae4', '#e6f5c9', '#fff2ae', '#f1e2cc', '#cccccc'],
    Pastel1: ['#fbb4ae', '#b3cde3', '#ccebc5', '#decbe4', '#fed9a6', '#ffffcc', '#e5d8bd', '#fddaec', '#f2f2f2']
  };

  (function() {
    var key, results;
    results = [];
    for (key in brewer) {
      results.push(brewer[key.toLowerCase()] = brewer[key]);
    }
    return results;
  })();


  /**
  	X11 color names
  
  	http://www.w3.org/TR/css3-color/#svg-color
   */

  w3cx11 = {
    aliceblue: '#f0f8ff',
    antiquewhite: '#faebd7',
    aqua: '#00ffff',
    aquamarine: '#7fffd4',
    azure: '#f0ffff',
    beige: '#f5f5dc',
    bisque: '#ffe4c4',
    black: '#000000',
    blanchedalmond: '#ffebcd',
    blue: '#0000ff',
    blueviolet: '#8a2be2',
    brown: '#a52a2a',
    burlywood: '#deb887',
    cadetblue: '#5f9ea0',
    chartreuse: '#7fff00',
    chocolate: '#d2691e',
    coral: '#ff7f50',
    cornflower: '#6495ed',
    cornflowerblue: '#6495ed',
    cornsilk: '#fff8dc',
    crimson: '#dc143c',
    cyan: '#00ffff',
    darkblue: '#00008b',
    darkcyan: '#008b8b',
    darkgoldenrod: '#b8860b',
    darkgray: '#a9a9a9',
    darkgreen: '#006400',
    darkgrey: '#a9a9a9',
    darkkhaki: '#bdb76b',
    darkmagenta: '#8b008b',
    darkolivegreen: '#556b2f',
    darkorange: '#ff8c00',
    darkorchid: '#9932cc',
    darkred: '#8b0000',
    darksalmon: '#e9967a',
    darkseagreen: '#8fbc8f',
    darkslateblue: '#483d8b',
    darkslategray: '#2f4f4f',
    darkslategrey: '#2f4f4f',
    darkturquoise: '#00ced1',
    darkviolet: '#9400d3',
    deeppink: '#ff1493',
    deepskyblue: '#00bfff',
    dimgray: '#696969',
    dimgrey: '#696969',
    dodgerblue: '#1e90ff',
    firebrick: '#b22222',
    floralwhite: '#fffaf0',
    forestgreen: '#228b22',
    fuchsia: '#ff00ff',
    gainsboro: '#dcdcdc',
    ghostwhite: '#f8f8ff',
    gold: '#ffd700',
    goldenrod: '#daa520',
    gray: '#808080',
    green: '#008000',
    greenyellow: '#adff2f',
    grey: '#808080',
    honeydew: '#f0fff0',
    hotpink: '#ff69b4',
    indianred: '#cd5c5c',
    indigo: '#4b0082',
    ivory: '#fffff0',
    khaki: '#f0e68c',
    laserlemon: '#ffff54',
    lavender: '#e6e6fa',
    lavenderblush: '#fff0f5',
    lawngreen: '#7cfc00',
    lemonchiffon: '#fffacd',
    lightblue: '#add8e6',
    lightcoral: '#f08080',
    lightcyan: '#e0ffff',
    lightgoldenrod: '#fafad2',
    lightgoldenrodyellow: '#fafad2',
    lightgray: '#d3d3d3',
    lightgreen: '#90ee90',
    lightgrey: '#d3d3d3',
    lightpink: '#ffb6c1',
    lightsalmon: '#ffa07a',
    lightseagreen: '#20b2aa',
    lightskyblue: '#87cefa',
    lightslategray: '#778899',
    lightslategrey: '#778899',
    lightsteelblue: '#b0c4de',
    lightyellow: '#ffffe0',
    lime: '#00ff00',
    limegreen: '#32cd32',
    linen: '#faf0e6',
    magenta: '#ff00ff',
    maroon: '#800000',
    maroon2: '#7f0000',
    maroon3: '#b03060',
    mediumaquamarine: '#66cdaa',
    mediumblue: '#0000cd',
    mediumorchid: '#ba55d3',
    mediumpurple: '#9370db',
    mediumseagreen: '#3cb371',
    mediumslateblue: '#7b68ee',
    mediumspringgreen: '#00fa9a',
    mediumturquoise: '#48d1cc',
    mediumvioletred: '#c71585',
    midnightblue: '#191970',
    mintcream: '#f5fffa',
    mistyrose: '#ffe4e1',
    moccasin: '#ffe4b5',
    navajowhite: '#ffdead',
    navy: '#000080',
    oldlace: '#fdf5e6',
    olive: '#808000',
    olivedrab: '#6b8e23',
    orange: '#ffa500',
    orangered: '#ff4500',
    orchid: '#da70d6',
    palegoldenrod: '#eee8aa',
    palegreen: '#98fb98',
    paleturquoise: '#afeeee',
    palevioletred: '#db7093',
    papayawhip: '#ffefd5',
    peachpuff: '#ffdab9',
    peru: '#cd853f',
    pink: '#ffc0cb',
    plum: '#dda0dd',
    powderblue: '#b0e0e6',
    purple: '#800080',
    purple2: '#7f007f',
    purple3: '#a020f0',
    rebeccapurple: '#663399',
    red: '#ff0000',
    rosybrown: '#bc8f8f',
    royalblue: '#4169e1',
    saddlebrown: '#8b4513',
    salmon: '#fa8072',
    sandybrown: '#f4a460',
    seagreen: '#2e8b57',
    seashell: '#fff5ee',
    sienna: '#a0522d',
    silver: '#c0c0c0',
    skyblue: '#87ceeb',
    slateblue: '#6a5acd',
    slategray: '#708090',
    slategrey: '#708090',
    snow: '#fffafa',
    springgreen: '#00ff7f',
    steelblue: '#4682b4',
    tan: '#d2b48c',
    teal: '#008080',
    thistle: '#d8bfd8',
    tomato: '#ff6347',
    turquoise: '#40e0d0',
    violet: '#ee82ee',
    wheat: '#f5deb3',
    white: '#ffffff',
    whitesmoke: '#f5f5f5',
    yellow: '#ffff00',
    yellowgreen: '#9acd32'
  };

  chroma.colors = colors = w3cx11;

  lab2rgb = function() {
    var a, args, b, g, l, r, x, y, z;
    args = unpack(arguments);
    l = args[0], a = args[1], b = args[2];
    y = (l + 16) / 116;
    x = isNaN(a) ? y : y + a / 500;
    z = isNaN(b) ? y : y - b / 200;
    y = LAB_CONSTANTS.Yn * lab_xyz(y);
    x = LAB_CONSTANTS.Xn * lab_xyz(x);
    z = LAB_CONSTANTS.Zn * lab_xyz(z);
    r = xyz_rgb(3.2404542 * x - 1.5371385 * y - 0.4985314 * z);
    g = xyz_rgb(-0.9692660 * x + 1.8760108 * y + 0.0415560 * z);
    b = xyz_rgb(0.0556434 * x - 0.2040259 * y + 1.0572252 * z);
    return [r, g, b, args.length > 3 ? args[3] : 1];
  };

  xyz_rgb = function(r) {
    return 255 * (r <= 0.00304 ? 12.92 * r : 1.055 * pow(r, 1 / 2.4) - 0.055);
  };

  lab_xyz = function(t) {
    if (t > LAB_CONSTANTS.t1) {
      return t * t * t;
    } else {
      return LAB_CONSTANTS.t2 * (t - LAB_CONSTANTS.t0);
    }
  };

  LAB_CONSTANTS = {
    Kn: 18,
    Xn: 0.950470,
    Yn: 1,
    Zn: 1.088830,
    t0: 0.137931034,
    t1: 0.206896552,
    t2: 0.12841855,
    t3: 0.008856452
  };

  rgb2lab = function() {
    var b, g, r, ref, ref1, x, y, z;
    ref = unpack(arguments), r = ref[0], g = ref[1], b = ref[2];
    ref1 = rgb2xyz(r, g, b), x = ref1[0], y = ref1[1], z = ref1[2];
    return [116 * y - 16, 500 * (x - y), 200 * (y - z)];
  };

  rgb_xyz = function(r) {
    if ((r /= 255) <= 0.04045) {
      return r / 12.92;
    } else {
      return pow((r + 0.055) / 1.055, 2.4);
    }
  };

  xyz_lab = function(t) {
    if (t > LAB_CONSTANTS.t3) {
      return pow(t, 1 / 3);
    } else {
      return t / LAB_CONSTANTS.t2 + LAB_CONSTANTS.t0;
    }
  };

  rgb2xyz = function() {
    var b, g, r, ref, x, y, z;
    ref = unpack(arguments), r = ref[0], g = ref[1], b = ref[2];
    r = rgb_xyz(r);
    g = rgb_xyz(g);
    b = rgb_xyz(b);
    x = xyz_lab((0.4124564 * r + 0.3575761 * g + 0.1804375 * b) / LAB_CONSTANTS.Xn);
    y = xyz_lab((0.2126729 * r + 0.7151522 * g + 0.0721750 * b) / LAB_CONSTANTS.Yn);
    z = xyz_lab((0.0193339 * r + 0.1191920 * g + 0.9503041 * b) / LAB_CONSTANTS.Zn);
    return [x, y, z];
  };

  chroma.lab = function() {
    return (function(func, args, ctor) {
      ctor.prototype = func.prototype;
      var child = new ctor, result = func.apply(child, args);
      return Object(result) === result ? result : child;
    })(Color, slice.call(arguments).concat(['lab']), function(){});
  };

  _input.lab = lab2rgb;

  Color.prototype.lab = function() {
    return rgb2lab(this._rgb);
  };

  bezier = function(colors) {
    var I, I0, I1, c, lab0, lab1, lab2, lab3, ref, ref1, ref2;
    colors = (function() {
      var len, o, results;
      results = [];
      for (o = 0, len = colors.length; o < len; o++) {
        c = colors[o];
        results.push(chroma(c));
      }
      return results;
    })();
    if (colors.length === 2) {
      ref = (function() {
        var len, o, results;
        results = [];
        for (o = 0, len = colors.length; o < len; o++) {
          c = colors[o];
          results.push(c.lab());
        }
        return results;
      })(), lab0 = ref[0], lab1 = ref[1];
      I = function(t) {
        var i, lab;
        lab = (function() {
          var o, results;
          results = [];
          for (i = o = 0; o <= 2; i = ++o) {
            results.push(lab0[i] + t * (lab1[i] - lab0[i]));
          }
          return results;
        })();
        return chroma.lab.apply(chroma, lab);
      };
    } else if (colors.length === 3) {
      ref1 = (function() {
        var len, o, results;
        results = [];
        for (o = 0, len = colors.length; o < len; o++) {
          c = colors[o];
          results.push(c.lab());
        }
        return results;
      })(), lab0 = ref1[0], lab1 = ref1[1], lab2 = ref1[2];
      I = function(t) {
        var i, lab;
        lab = (function() {
          var o, results;
          results = [];
          for (i = o = 0; o <= 2; i = ++o) {
            results.push((1 - t) * (1 - t) * lab0[i] + 2 * (1 - t) * t * lab1[i] + t * t * lab2[i]);
          }
          return results;
        })();
        return chroma.lab.apply(chroma, lab);
      };
    } else if (colors.length === 4) {
      ref2 = (function() {
        var len, o, results;
        results = [];
        for (o = 0, len = colors.length; o < len; o++) {
          c = colors[o];
          results.push(c.lab());
        }
        return results;
      })(), lab0 = ref2[0], lab1 = ref2[1], lab2 = ref2[2], lab3 = ref2[3];
      I = function(t) {
        var i, lab;
        lab = (function() {
          var o, results;
          results = [];
          for (i = o = 0; o <= 2; i = ++o) {
            results.push((1 - t) * (1 - t) * (1 - t) * lab0[i] + 3 * (1 - t) * (1 - t) * t * lab1[i] + 3 * (1 - t) * t * t * lab2[i] + t * t * t * lab3[i]);
          }
          return results;
        })();
        return chroma.lab.apply(chroma, lab);
      };
    } else if (colors.length === 5) {
      I0 = bezier(colors.slice(0, 3));
      I1 = bezier(colors.slice(2, 5));
      I = function(t) {
        if (t < 0.5) {
          return I0(t * 2);
        } else {
          return I1((t - 0.5) * 2);
        }
      };
    }
    return I;
  };

  chroma.bezier = function(colors) {
    var f;
    f = bezier(colors);
    f.scale = function() {
      return chroma.scale(f);
    };
    return f;
  };

  chroma.cubehelix = function(start, rotations, hue, gamma, lightness) {
    var dh, dl, f;
    if (start == null) {
      start = 300;
    }
    if (rotations == null) {
      rotations = -1.5;
    }
    if (hue == null) {
      hue = 1;
    }
    if (gamma == null) {
      gamma = 1;
    }
    if (lightness == null) {
      lightness = [0, 1];
    }
    dh = 0;
    if (type(lightness) === 'array') {
      dl = lightness[1] - lightness[0];
    } else {
      dl = 0;
      lightness = [lightness, lightness];
    }
    f = function(fract) {
      var a, amp, b, cos_a, g, h, l, r, sin_a;
      a = TWOPI * ((start + 120) / 360 + rotations * fract);
      l = pow(lightness[0] + dl * fract, gamma);
      h = dh !== 0 ? hue[0] + fract * dh : hue;
      amp = h * l * (1 - l) / 2;
      cos_a = cos(a);
      sin_a = sin(a);
      r = l + amp * (-0.14861 * cos_a + 1.78277 * sin_a);
      g = l + amp * (-0.29227 * cos_a - 0.90649 * sin_a);
      b = l + amp * (+1.97294 * cos_a);
      return chroma(clip_rgb([r * 255, g * 255, b * 255, 1]));
    };
    f.start = function(s) {
      if (s == null) {
        return start;
      }
      start = s;
      return f;
    };
    f.rotations = function(r) {
      if (r == null) {
        return rotations;
      }
      rotations = r;
      return f;
    };
    f.gamma = function(g) {
      if (g == null) {
        return gamma;
      }
      gamma = g;
      return f;
    };
    f.hue = function(h) {
      if (h == null) {
        return hue;
      }
      hue = h;
      if (type(hue) === 'array') {
        dh = hue[1] - hue[0];
        if (dh === 0) {
          hue = hue[1];
        }
      } else {
        dh = 0;
      }
      return f;
    };
    f.lightness = function(h) {
      if (h == null) {
        return lightness;
      }
      if (type(h) === 'array') {
        lightness = h;
        dl = h[1] - h[0];
      } else {
        lightness = [h, h];
        dl = 0;
      }
      return f;
    };
    f.scale = function() {
      return chroma.scale(f);
    };
    f.hue(hue);
    return f;
  };

  chroma.random = function() {
    var code, digits, i, o;
    digits = '0123456789abcdef';
    code = '#';
    for (i = o = 0; o < 6; i = ++o) {
      code += digits.charAt(floor(Math.random() * 16));
    }
    return new Color(code);
  };

  _interpolators = [];

  interpolate = function(col1, col2, f, m) {
    var interpol, len, o, res;
    if (f == null) {
      f = 0.5;
    }
    if (m == null) {
      m = 'rgb';
    }

    /*
    interpolates between colors
    f = 0 --> me
    f = 1 --> col
     */
    if (type(col1) !== 'object') {
      col1 = chroma(col1);
    }
    if (type(col2) !== 'object') {
      col2 = chroma(col2);
    }
    for (o = 0, len = _interpolators.length; o < len; o++) {
      interpol = _interpolators[o];
      if (m === interpol[0]) {
        res = interpol[1](col1, col2, f, m);
        break;
      }
    }
    if (res == null) {
      throw "color mode " + m + " is not supported";
    }
    return res.alpha(col1.alpha() + f * (col2.alpha() - col1.alpha()));
  };

  chroma.interpolate = interpolate;

  Color.prototype.interpolate = function(col2, f, m) {
    return interpolate(this, col2, f, m);
  };

  chroma.mix = interpolate;

  Color.prototype.mix = Color.prototype.interpolate;

  _input.rgb = function() {
    var k, ref, results, v;
    ref = unpack(arguments);
    results = [];
    for (k in ref) {
      v = ref[k];
      results.push(v);
    }
    return results;
  };

  chroma.rgb = function() {
    return (function(func, args, ctor) {
      ctor.prototype = func.prototype;
      var child = new ctor, result = func.apply(child, args);
      return Object(result) === result ? result : child;
    })(Color, slice.call(arguments).concat(['rgb']), function(){});
  };

  Color.prototype.rgb = function(round) {
    if (round == null) {
      round = true;
    }
    if (round) {
      return this._rgb.map(Math.round).slice(0, 3);
    } else {
      return this._rgb.slice(0, 3);
    }
  };

  Color.prototype.rgba = function(round) {
    if (round == null) {
      round = true;
    }
    if (!round) {
      return this._rgb.slice(0);
    }
    return [Math.round(this._rgb[0]), Math.round(this._rgb[1]), Math.round(this._rgb[2]), this._rgb[3]];
  };

  _guess_formats.push({
    p: 3,
    test: function(n) {
      var a;
      a = unpack(arguments);
      if (type(a) === 'array' && a.length === 3) {
        return 'rgb';
      }
      if (a.length === 4 && type(a[3]) === "number" && a[3] >= 0 && a[3] <= 1) {
        return 'rgb';
      }
    }
  });

  _input.lrgb = _input.rgb;

  interpolate_lrgb = function(col1, col2, f, m) {
    var xyz0, xyz1;
    xyz0 = col1._rgb;
    xyz1 = col2._rgb;
    return new Color(sqrt(pow(xyz0[0], 2) * (1 - f) + pow(xyz1[0], 2) * f), sqrt(pow(xyz0[1], 2) * (1 - f) + pow(xyz1[1], 2) * f), sqrt(pow(xyz0[2], 2) * (1 - f) + pow(xyz1[2], 2) * f), m);
  };

  _average_lrgb = function(colors) {
    var col, f, len, o, rgb, xyz;
    f = 1 / colors.length;
    xyz = [0, 0, 0, 0];
    for (o = 0, len = colors.length; o < len; o++) {
      col = colors[o];
      rgb = col._rgb;
      xyz[0] += pow(rgb[0], 2) * f;
      xyz[1] += pow(rgb[1], 2) * f;
      xyz[2] += pow(rgb[2], 2) * f;
      xyz[3] += rgb[3] * f;
    }
    xyz[0] = sqrt(xyz[0]);
    xyz[1] = sqrt(xyz[1]);
    xyz[2] = sqrt(xyz[2]);
    if (xyz[3] > 1) {
      xyz[3] = 1;
    }
    return new Color(clip_rgb(xyz));
  };

  _interpolators.push(['lrgb', interpolate_lrgb]);

  chroma.average = function(colors, mode) {
    var A, alpha, c, cnt, dx, dy, first, i, l, len, o, xyz, xyz2;
    if (mode == null) {
      mode = 'rgb';
    }
    l = colors.length;
    colors = colors.map(function(c) {
      return chroma(c);
    });
    first = colors.splice(0, 1)[0];
    if (mode === 'lrgb') {
      return _average_lrgb(colors);
    }
    xyz = first.get(mode);
    cnt = [];
    dx = 0;
    dy = 0;
    for (i in xyz) {
      xyz[i] = xyz[i] || 0;
      cnt.push(isNaN(xyz[i]) ? 0 : 1);
      if (mode.charAt(i) === 'h' && !isNaN(xyz[i])) {
        A = xyz[i] / 180 * PI;
        dx += cos(A);
        dy += sin(A);
      }
    }
    alpha = first.alpha();
    for (o = 0, len = colors.length; o < len; o++) {
      c = colors[o];
      xyz2 = c.get(mode);
      alpha += c.alpha();
      for (i in xyz) {
        if (!isNaN(xyz2[i])) {
          cnt[i] += 1;
          if (mode.charAt(i) === 'h') {
            A = xyz2[i] / 180 * PI;
            dx += cos(A);
            dy += sin(A);
          } else {
            xyz[i] += xyz2[i];
          }
        }
      }
    }
    for (i in xyz) {
      if (mode.charAt(i) === 'h') {
        A = atan2(dy / cnt[i], dx / cnt[i]) / PI * 180;
        while (A < 0) {
          A += 360;
        }
        while (A >= 360) {
          A -= 360;
        }
        xyz[i] = A;
      } else {
        xyz[i] = xyz[i] / cnt[i];
      }
    }
    return chroma(xyz, mode).alpha(alpha / l);
  };

  hex2rgb = function(hex) {
    var a, b, g, r, rgb, u;
    if (hex.match(/^#?([A-Fa-f0-9]{6}|[A-Fa-f0-9]{3})$/)) {
      if (hex.length === 4 || hex.length === 7) {
        hex = hex.substr(1);
      }
      if (hex.length === 3) {
        hex = hex.split("");
        hex = hex[0] + hex[0] + hex[1] + hex[1] + hex[2] + hex[2];
      }
      u = parseInt(hex, 16);
      r = u >> 16;
      g = u >> 8 & 0xFF;
      b = u & 0xFF;
      return [r, g, b, 1];
    }
    if (hex.match(/^#?([A-Fa-f0-9]{8})$/)) {
      if (hex.length === 9) {
        hex = hex.substr(1);
      }
      u = parseInt(hex, 16);
      r = u >> 24 & 0xFF;
      g = u >> 16 & 0xFF;
      b = u >> 8 & 0xFF;
      a = round((u & 0xFF) / 0xFF * 100) / 100;
      return [r, g, b, a];
    }
    if ((_input.css != null) && (rgb = _input.css(hex))) {
      return rgb;
    }
    throw "unknown color: " + hex;
  };

  rgb2hex = function(channels, mode) {
    var a, b, g, hxa, r, str, u;
    if (mode == null) {
      mode = 'auto';
    }
    r = channels[0], g = channels[1], b = channels[2], a = channels[3];
    if (mode === 'auto') {
      mode = a < 1 ? 'rgba' : 'rgb';
    }
    r = Math.round(r);
    g = Math.round(g);
    b = Math.round(b);
    u = r << 16 | g << 8 | b;
    str = "000000" + u.toString(16);
    str = str.substr(str.length - 6);
    hxa = '0' + round(a * 255).toString(16);
    hxa = hxa.substr(hxa.length - 2);
    return "#" + (function() {
      switch (mode.toLowerCase()) {
        case 'rgba':
          return str + hxa;
        case 'argb':
          return hxa + str;
        default:
          return str;
      }
    })();
  };

  _input.hex = function(h) {
    return hex2rgb(h);
  };

  chroma.hex = function() {
    return (function(func, args, ctor) {
      ctor.prototype = func.prototype;
      var child = new ctor, result = func.apply(child, args);
      return Object(result) === result ? result : child;
    })(Color, slice.call(arguments).concat(['hex']), function(){});
  };

  Color.prototype.hex = function(mode) {
    if (mode == null) {
      mode = 'auto';
    }
    return rgb2hex(this._rgb, mode);
  };

  _guess_formats.push({
    p: 4,
    test: function(n) {
      if (arguments.length === 1 && type(n) === "string") {
        return 'hex';
      }
    }
  });

  hsl2rgb = function() {
    var args, b, c, g, h, i, l, o, r, ref, s, t1, t2, t3;
    args = unpack(arguments);
    h = args[0], s = args[1], l = args[2];
    if (s === 0) {
      r = g = b = l * 255;
    } else {
      t3 = [0, 0, 0];
      c = [0, 0, 0];
      t2 = l < 0.5 ? l * (1 + s) : l + s - l * s;
      t1 = 2 * l - t2;
      h /= 360;
      t3[0] = h + 1 / 3;
      t3[1] = h;
      t3[2] = h - 1 / 3;
      for (i = o = 0; o <= 2; i = ++o) {
        if (t3[i] < 0) {
          t3[i] += 1;
        }
        if (t3[i] > 1) {
          t3[i] -= 1;
        }
        if (6 * t3[i] < 1) {
          c[i] = t1 + (t2 - t1) * 6 * t3[i];
        } else if (2 * t3[i] < 1) {
          c[i] = t2;
        } else if (3 * t3[i] < 2) {
          c[i] = t1 + (t2 - t1) * ((2 / 3) - t3[i]) * 6;
        } else {
          c[i] = t1;
        }
      }
      ref = [round(c[0] * 255), round(c[1] * 255), round(c[2] * 255)], r = ref[0], g = ref[1], b = ref[2];
    }
    if (args.length > 3) {
      return [r, g, b, args[3]];
    } else {
      return [r, g, b];
    }
  };

  rgb2hsl = function(r, g, b) {
    var h, l, min, ref, s;
    if (r !== void 0 && r.length >= 3) {
      ref = r, r = ref[0], g = ref[1], b = ref[2];
    }
    r /= 255;
    g /= 255;
    b /= 255;
    min = Math.min(r, g, b);
    max = Math.max(r, g, b);
    l = (max + min) / 2;
    if (max === min) {
      s = 0;
      h = Number.NaN;
    } else {
      s = l < 0.5 ? (max - min) / (max + min) : (max - min) / (2 - max - min);
    }
    if (r === max) {
      h = (g - b) / (max - min);
    } else if (g === max) {
      h = 2 + (b - r) / (max - min);
    } else if (b === max) {
      h = 4 + (r - g) / (max - min);
    }
    h *= 60;
    if (h < 0) {
      h += 360;
    }
    return [h, s, l];
  };

  chroma.hsl = function() {
    return (function(func, args, ctor) {
      ctor.prototype = func.prototype;
      var child = new ctor, result = func.apply(child, args);
      return Object(result) === result ? result : child;
    })(Color, slice.call(arguments).concat(['hsl']), function(){});
  };

  _input.hsl = hsl2rgb;

  Color.prototype.hsl = function() {
    return rgb2hsl(this._rgb);
  };

  hsv2rgb = function() {
    var args, b, f, g, h, i, p, q, r, ref, ref1, ref2, ref3, ref4, ref5, s, t, v;
    args = unpack(arguments);
    h = args[0], s = args[1], v = args[2];
    v *= 255;
    if (s === 0) {
      r = g = b = v;
    } else {
      if (h === 360) {
        h = 0;
      }
      if (h > 360) {
        h -= 360;
      }
      if (h < 0) {
        h += 360;
      }
      h /= 60;
      i = floor(h);
      f = h - i;
      p = v * (1 - s);
      q = v * (1 - s * f);
      t = v * (1 - s * (1 - f));
      switch (i) {
        case 0:
          ref = [v, t, p], r = ref[0], g = ref[1], b = ref[2];
          break;
        case 1:
          ref1 = [q, v, p], r = ref1[0], g = ref1[1], b = ref1[2];
          break;
        case 2:
          ref2 = [p, v, t], r = ref2[0], g = ref2[1], b = ref2[2];
          break;
        case 3:
          ref3 = [p, q, v], r = ref3[0], g = ref3[1], b = ref3[2];
          break;
        case 4:
          ref4 = [t, p, v], r = ref4[0], g = ref4[1], b = ref4[2];
          break;
        case 5:
          ref5 = [v, p, q], r = ref5[0], g = ref5[1], b = ref5[2];
      }
    }
    return [r, g, b, args.length > 3 ? args[3] : 1];
  };

  rgb2hsv = function() {
    var b, delta, g, h, min, r, ref, s, v;
    ref = unpack(arguments), r = ref[0], g = ref[1], b = ref[2];
    min = Math.min(r, g, b);
    max = Math.max(r, g, b);
    delta = max - min;
    v = max / 255.0;
    if (max === 0) {
      h = Number.NaN;
      s = 0;
    } else {
      s = delta / max;
      if (r === max) {
        h = (g - b) / delta;
      }
      if (g === max) {
        h = 2 + (b - r) / delta;
      }
      if (b === max) {
        h = 4 + (r - g) / delta;
      }
      h *= 60;
      if (h < 0) {
        h += 360;
      }
    }
    return [h, s, v];
  };

  chroma.hsv = function() {
    return (function(func, args, ctor) {
      ctor.prototype = func.prototype;
      var child = new ctor, result = func.apply(child, args);
      return Object(result) === result ? result : child;
    })(Color, slice.call(arguments).concat(['hsv']), function(){});
  };

  _input.hsv = hsv2rgb;

  Color.prototype.hsv = function() {
    return rgb2hsv(this._rgb);
  };

  num2rgb = function(num) {
    var b, g, r;
    if (type(num) === "number" && num >= 0 && num <= 0xFFFFFF) {
      r = num >> 16;
      g = (num >> 8) & 0xFF;
      b = num & 0xFF;
      return [r, g, b, 1];
    }
    console.warn("unknown num color: " + num);
    return [0, 0, 0, 1];
  };

  rgb2num = function() {
    var b, g, r, ref;
    ref = unpack(arguments), r = ref[0], g = ref[1], b = ref[2];
    return (r << 16) + (g << 8) + b;
  };

  chroma.num = function(num) {
    return new Color(num, 'num');
  };

  Color.prototype.num = function(mode) {
    if (mode == null) {
      mode = 'rgb';
    }
    return rgb2num(this._rgb, mode);
  };

  _input.num = num2rgb;

  _guess_formats.push({
    p: 1,
    test: function(n) {
      if (arguments.length === 1 && type(n) === "number" && n >= 0 && n <= 0xFFFFFF) {
        return 'num';
      }
    }
  });

  hcg2rgb = function() {
    var _c, _g, args, b, c, f, g, h, i, p, q, r, ref, ref1, ref2, ref3, ref4, ref5, t, v;
    args = unpack(arguments);
    h = args[0], c = args[1], _g = args[2];
    c = c / 100;
    g = g / 100 * 255;
    _c = c * 255;
    if (c === 0) {
      r = g = b = _g;
    } else {
      if (h === 360) {
        h = 0;
      }
      if (h > 360) {
        h -= 360;
      }
      if (h < 0) {
        h += 360;
      }
      h /= 60;
      i = floor(h);
      f = h - i;
      p = _g * (1 - c);
      q = p + _c * (1 - f);
      t = p + _c * f;
      v = p + _c;
      switch (i) {
        case 0:
          ref = [v, t, p], r = ref[0], g = ref[1], b = ref[2];
          break;
        case 1:
          ref1 = [q, v, p], r = ref1[0], g = ref1[1], b = ref1[2];
          break;
        case 2:
          ref2 = [p, v, t], r = ref2[0], g = ref2[1], b = ref2[2];
          break;
        case 3:
          ref3 = [p, q, v], r = ref3[0], g = ref3[1], b = ref3[2];
          break;
        case 4:
          ref4 = [t, p, v], r = ref4[0], g = ref4[1], b = ref4[2];
          break;
        case 5:
          ref5 = [v, p, q], r = ref5[0], g = ref5[1], b = ref5[2];
      }
    }
    return [r, g, b, args.length > 3 ? args[3] : 1];
  };

  rgb2hcg = function() {
    var _g, b, c, delta, g, h, min, r, ref;
    ref = unpack(arguments), r = ref[0], g = ref[1], b = ref[2];
    min = Math.min(r, g, b);
    max = Math.max(r, g, b);
    delta = max - min;
    c = delta * 100 / 255;
    _g = min / (255 - delta) * 100;
    if (delta === 0) {
      h = Number.NaN;
    } else {
      if (r === max) {
        h = (g - b) / delta;
      }
      if (g === max) {
        h = 2 + (b - r) / delta;
      }
      if (b === max) {
        h = 4 + (r - g) / delta;
      }
      h *= 60;
      if (h < 0) {
        h += 360;
      }
    }
    return [h, c, _g];
  };

  chroma.hcg = function() {
    return (function(func, args, ctor) {
      ctor.prototype = func.prototype;
      var child = new ctor, result = func.apply(child, args);
      return Object(result) === result ? result : child;
    })(Color, slice.call(arguments).concat(['hcg']), function(){});
  };

  _input.hcg = hcg2rgb;

  Color.prototype.hcg = function() {
    return rgb2hcg(this._rgb);
  };

  css2rgb = function(css) {
    var aa, ab, hsl, i, m, o, rgb, w;
    css = css.toLowerCase();
    if ((chroma.colors != null) && chroma.colors[css]) {
      return hex2rgb(chroma.colors[css]);
    }
    if (m = css.match(/rgb\(\s*(\-?\d+),\s*(\-?\d+)\s*,\s*(\-?\d+)\s*\)/)) {
      rgb = m.slice(1, 4);
      for (i = o = 0; o <= 2; i = ++o) {
        rgb[i] = +rgb[i];
      }
      rgb[3] = 1;
    } else if (m = css.match(/rgba\(\s*(\-?\d+),\s*(\-?\d+)\s*,\s*(\-?\d+)\s*,\s*([01]|[01]?\.\d+)\)/)) {
      rgb = m.slice(1, 5);
      for (i = w = 0; w <= 3; i = ++w) {
        rgb[i] = +rgb[i];
      }
    } else if (m = css.match(/rgb\(\s*(\-?\d+(?:\.\d+)?)%,\s*(\-?\d+(?:\.\d+)?)%\s*,\s*(\-?\d+(?:\.\d+)?)%\s*\)/)) {
      rgb = m.slice(1, 4);
      for (i = aa = 0; aa <= 2; i = ++aa) {
        rgb[i] = round(rgb[i] * 2.55);
      }
      rgb[3] = 1;
    } else if (m = css.match(/rgba\(\s*(\-?\d+(?:\.\d+)?)%,\s*(\-?\d+(?:\.\d+)?)%\s*,\s*(\-?\d+(?:\.\d+)?)%\s*,\s*([01]|[01]?\.\d+)\)/)) {
      rgb = m.slice(1, 5);
      for (i = ab = 0; ab <= 2; i = ++ab) {
        rgb[i] = round(rgb[i] * 2.55);
      }
      rgb[3] = +rgb[3];
    } else if (m = css.match(/hsl\(\s*(\-?\d+(?:\.\d+)?),\s*(\-?\d+(?:\.\d+)?)%\s*,\s*(\-?\d+(?:\.\d+)?)%\s*\)/)) {
      hsl = m.slice(1, 4);
      hsl[1] *= 0.01;
      hsl[2] *= 0.01;
      rgb = hsl2rgb(hsl);
      rgb[3] = 1;
    } else if (m = css.match(/hsla\(\s*(\-?\d+(?:\.\d+)?),\s*(\-?\d+(?:\.\d+)?)%\s*,\s*(\-?\d+(?:\.\d+)?)%\s*,\s*([01]|[01]?\.\d+)\)/)) {
      hsl = m.slice(1, 4);
      hsl[1] *= 0.01;
      hsl[2] *= 0.01;
      rgb = hsl2rgb(hsl);
      rgb[3] = +m[4];
    }
    return rgb;
  };

  rgb2css = function(rgba) {
    var mode;
    mode = rgba[3] < 1 ? 'rgba' : 'rgb';
    if (mode === 'rgb') {
      return mode + '(' + rgba.slice(0, 3).map(round).join(',') + ')';
    } else if (mode === 'rgba') {
      return mode + '(' + rgba.slice(0, 3).map(round).join(',') + ',' + rgba[3] + ')';
    } else {

    }
  };

  rnd = function(a) {
    return round(a * 100) / 100;
  };

  hsl2css = function(hsl, alpha) {
    var mode;
    mode = alpha < 1 ? 'hsla' : 'hsl';
    hsl[0] = rnd(hsl[0] || 0);
    hsl[1] = rnd(hsl[1] * 100) + '%';
    hsl[2] = rnd(hsl[2] * 100) + '%';
    if (mode === 'hsla') {
      hsl[3] = alpha;
    }
    return mode + '(' + hsl.join(',') + ')';
  };

  _input.css = function(h) {
    return css2rgb(h);
  };

  chroma.css = function() {
    return (function(func, args, ctor) {
      ctor.prototype = func.prototype;
      var child = new ctor, result = func.apply(child, args);
      return Object(result) === result ? result : child;
    })(Color, slice.call(arguments).concat(['css']), function(){});
  };

  Color.prototype.css = function(mode) {
    if (mode == null) {
      mode = 'rgb';
    }
    if (mode.slice(0, 3) === 'rgb') {
      return rgb2css(this._rgb);
    } else if (mode.slice(0, 3) === 'hsl') {
      return hsl2css(this.hsl(), this.alpha());
    }
  };

  _input.named = function(name) {
    return hex2rgb(w3cx11[name]);
  };

  _guess_formats.push({
    p: 5,
    test: function(n) {
      if (arguments.length === 1 && (w3cx11[n] != null)) {
        return 'named';
      }
    }
  });

  Color.prototype.name = function(n) {
    var h, k;
    if (arguments.length) {
      if (w3cx11[n]) {
        this._rgb = hex2rgb(w3cx11[n]);
      }
      this._rgb[3] = 1;
      this;
    }
    h = this.hex('rgb');
    for (k in w3cx11) {
      if (h === w3cx11[k]) {
        return k;
      }
    }
    return h;
  };

  lch2lab = function() {

    /*
    Convert from a qualitative parameter h and a quantitative parameter l to a 24-bit pixel.
    These formulas were invented by David Dalrymple to obtain maximum contrast without going
    out of gamut if the parameters are in the range 0-1.
    
    A saturation multiplier was added by Gregor Aisch
     */
    var c, h, l, ref;
    ref = unpack(arguments), l = ref[0], c = ref[1], h = ref[2];
    h = h * DEG2RAD;
    return [l, cos(h) * c, sin(h) * c];
  };

  lch2rgb = function() {
    var L, a, args, b, c, g, h, l, r, ref, ref1;
    args = unpack(arguments);
    l = args[0], c = args[1], h = args[2];
    ref = lch2lab(l, c, h), L = ref[0], a = ref[1], b = ref[2];
    ref1 = lab2rgb(L, a, b), r = ref1[0], g = ref1[1], b = ref1[2];
    return [r, g, b, args.length > 3 ? args[3] : 1];
  };

  lab2lch = function() {
    var a, b, c, h, l, ref;
    ref = unpack(arguments), l = ref[0], a = ref[1], b = ref[2];
    c = sqrt(a * a + b * b);
    h = (atan2(b, a) * RAD2DEG + 360) % 360;
    if (round(c * 10000) === 0) {
      h = Number.NaN;
    }
    return [l, c, h];
  };

  rgb2lch = function() {
    var a, b, g, l, r, ref, ref1;
    ref = unpack(arguments), r = ref[0], g = ref[1], b = ref[2];
    ref1 = rgb2lab(r, g, b), l = ref1[0], a = ref1[1], b = ref1[2];
    return lab2lch(l, a, b);
  };

  chroma.lch = function() {
    var args;
    args = unpack(arguments);
    return new Color(args, 'lch');
  };

  chroma.hcl = function() {
    var args;
    args = unpack(arguments);
    return new Color(args, 'hcl');
  };

  _input.lch = lch2rgb;

  _input.hcl = function() {
    var c, h, l, ref;
    ref = unpack(arguments), h = ref[0], c = ref[1], l = ref[2];
    return lch2rgb([l, c, h]);
  };

  Color.prototype.lch = function() {
    return rgb2lch(this._rgb);
  };

  Color.prototype.hcl = function() {
    return rgb2lch(this._rgb).reverse();
  };

  rgb2cmyk = function(mode) {
    var b, c, f, g, k, m, r, ref, y;
    if (mode == null) {
      mode = 'rgb';
    }
    ref = unpack(arguments), r = ref[0], g = ref[1], b = ref[2];
    r = r / 255;
    g = g / 255;
    b = b / 255;
    k = 1 - Math.max(r, Math.max(g, b));
    f = k < 1 ? 1 / (1 - k) : 0;
    c = (1 - r - k) * f;
    m = (1 - g - k) * f;
    y = (1 - b - k) * f;
    return [c, m, y, k];
  };

  cmyk2rgb = function() {
    var alpha, args, b, c, g, k, m, r, y;
    args = unpack(arguments);
    c = args[0], m = args[1], y = args[2], k = args[3];
    alpha = args.length > 4 ? args[4] : 1;
    if (k === 1) {
      return [0, 0, 0, alpha];
    }
    r = c >= 1 ? 0 : 255 * (1 - c) * (1 - k);
    g = m >= 1 ? 0 : 255 * (1 - m) * (1 - k);
    b = y >= 1 ? 0 : 255 * (1 - y) * (1 - k);
    return [r, g, b, alpha];
  };

  _input.cmyk = function() {
    return cmyk2rgb(unpack(arguments));
  };

  chroma.cmyk = function() {
    return (function(func, args, ctor) {
      ctor.prototype = func.prototype;
      var child = new ctor, result = func.apply(child, args);
      return Object(result) === result ? result : child;
    })(Color, slice.call(arguments).concat(['cmyk']), function(){});
  };

  Color.prototype.cmyk = function() {
    return rgb2cmyk(this._rgb);
  };

  _input.gl = function() {
    var i, k, o, rgb, v;
    rgb = (function() {
      var ref, results;
      ref = unpack(arguments);
      results = [];
      for (k in ref) {
        v = ref[k];
        results.push(v);
      }
      return results;
    }).apply(this, arguments);
    for (i = o = 0; o <= 2; i = ++o) {
      rgb[i] *= 255;
    }
    return rgb;
  };

  chroma.gl = function() {
    return (function(func, args, ctor) {
      ctor.prototype = func.prototype;
      var child = new ctor, result = func.apply(child, args);
      return Object(result) === result ? result : child;
    })(Color, slice.call(arguments).concat(['gl']), function(){});
  };

  Color.prototype.gl = function() {
    var rgb;
    rgb = this._rgb;
    return [rgb[0] / 255, rgb[1] / 255, rgb[2] / 255, rgb[3]];
  };

  rgb2luminance = function(r, g, b) {
    var ref;
    ref = unpack(arguments), r = ref[0], g = ref[1], b = ref[2];
    r = luminance_x(r);
    g = luminance_x(g);
    b = luminance_x(b);
    return 0.2126 * r + 0.7152 * g + 0.0722 * b;
  };

  luminance_x = function(x) {
    x /= 255;
    if (x <= 0.03928) {
      return x / 12.92;
    } else {
      return pow((x + 0.055) / 1.055, 2.4);
    }
  };

  interpolate_rgb = function(col1, col2, f, m) {
    var xyz0, xyz1;
    xyz0 = col1._rgb;
    xyz1 = col2._rgb;
    return new Color(xyz0[0] + f * (xyz1[0] - xyz0[0]), xyz0[1] + f * (xyz1[1] - xyz0[1]), xyz0[2] + f * (xyz1[2] - xyz0[2]), m);
  };

  _interpolators.push(['rgb', interpolate_rgb]);

  Color.prototype.luminance = function(lum, mode) {
    var cur_lum, eps, max_iter, rgba, test;
    if (mode == null) {
      mode = 'rgb';
    }
    if (!arguments.length) {
      return rgb2luminance(this._rgb);
    }
    rgba = this._rgb;
    if (lum === 0) {
      rgba = [0, 0, 0, this._rgb[3]];
    } else if (lum === 1) {
      rgba = [255, 255, 255, this[3]];
    } else {
      cur_lum = rgb2luminance(this._rgb);
      eps = 1e-7;
      max_iter = 20;
      test = function(l, h) {
        var lm, m;
        m = l.interpolate(h, 0.5, mode);
        lm = m.luminance();
        if (Math.abs(lum - lm) < eps || !max_iter--) {
          return m;
        }
        if (lm > lum) {
          return test(l, m);
        }
        return test(m, h);
      };
      if (cur_lum > lum) {
        rgba = test(chroma('black'), this).rgba();
      } else {
        rgba = test(this, chroma('white')).rgba();
      }
    }
    return chroma(rgba).alpha(this.alpha());
  };

  temperature2rgb = function(kelvin) {
    var b, g, r, temp;
    temp = kelvin / 100;
    if (temp < 66) {
      r = 255;
      g = -155.25485562709179 - 0.44596950469579133 * (g = temp - 2) + 104.49216199393888 * log(g);
      b = temp < 20 ? 0 : -254.76935184120902 + 0.8274096064007395 * (b = temp - 10) + 115.67994401066147 * log(b);
    } else {
      r = 351.97690566805693 + 0.114206453784165 * (r = temp - 55) - 40.25366309332127 * log(r);
      g = 325.4494125711974 + 0.07943456536662342 * (g = temp - 50) - 28.0852963507957 * log(g);
      b = 255;
    }
    return [r, g, b];
  };

  rgb2temperature = function() {
    var b, eps, g, maxTemp, minTemp, r, ref, rgb, temp;
    ref = unpack(arguments), r = ref[0], g = ref[1], b = ref[2];
    minTemp = 1000;
    maxTemp = 40000;
    eps = 0.4;
    while (maxTemp - minTemp > eps) {
      temp = (maxTemp + minTemp) * 0.5;
      rgb = temperature2rgb(temp);
      if ((rgb[2] / rgb[0]) >= (b / r)) {
        maxTemp = temp;
      } else {
        minTemp = temp;
      }
    }
    return round(temp);
  };

  chroma.temperature = chroma.kelvin = function() {
    return (function(func, args, ctor) {
      ctor.prototype = func.prototype;
      var child = new ctor, result = func.apply(child, args);
      return Object(result) === result ? result : child;
    })(Color, slice.call(arguments).concat(['temperature']), function(){});
  };

  _input.temperature = _input.kelvin = _input.K = temperature2rgb;

  Color.prototype.temperature = function() {
    return rgb2temperature(this._rgb);
  };

  Color.prototype.kelvin = Color.prototype.temperature;

  chroma.contrast = function(a, b) {
    var l1, l2, ref, ref1;
    if ((ref = type(a)) === 'string' || ref === 'number') {
      a = new Color(a);
    }
    if ((ref1 = type(b)) === 'string' || ref1 === 'number') {
      b = new Color(b);
    }
    l1 = a.luminance();
    l2 = b.luminance();
    if (l1 > l2) {
      return (l1 + 0.05) / (l2 + 0.05);
    } else {
      return (l2 + 0.05) / (l1 + 0.05);
    }
  };

  chroma.distance = function(a, b, mode) {
    var d, i, l1, l2, ref, ref1, sum_sq;
    if (mode == null) {
      mode = 'lab';
    }
    if ((ref = type(a)) === 'string' || ref === 'number') {
      a = new Color(a);
    }
    if ((ref1 = type(b)) === 'string' || ref1 === 'number') {
      b = new Color(b);
    }
    l1 = a.get(mode);
    l2 = b.get(mode);
    sum_sq = 0;
    for (i in l1) {
      d = (l1[i] || 0) - (l2[i] || 0);
      sum_sq += d * d;
    }
    return Math.sqrt(sum_sq);
  };

  chroma.deltaE = function(a, b, L, C) {
    var L1, L2, a1, a2, b1, b2, c1, c2, c4, dH2, delA, delB, delC, delL, f, h1, ref, ref1, ref2, ref3, sc, sh, sl, t, v1, v2, v3;
    if (L == null) {
      L = 1;
    }
    if (C == null) {
      C = 1;
    }
    if ((ref = type(a)) === 'string' || ref === 'number') {
      a = new Color(a);
    }
    if ((ref1 = type(b)) === 'string' || ref1 === 'number') {
      b = new Color(b);
    }
    ref2 = a.lab(), L1 = ref2[0], a1 = ref2[1], b1 = ref2[2];
    ref3 = b.lab(), L2 = ref3[0], a2 = ref3[1], b2 = ref3[2];
    c1 = sqrt(a1 * a1 + b1 * b1);
    c2 = sqrt(a2 * a2 + b2 * b2);
    sl = L1 < 16.0 ? 0.511 : (0.040975 * L1) / (1.0 + 0.01765 * L1);
    sc = (0.0638 * c1) / (1.0 + 0.0131 * c1) + 0.638;
    h1 = c1 < 0.000001 ? 0.0 : (atan2(b1, a1) * 180.0) / PI;
    while (h1 < 0) {
      h1 += 360;
    }
    while (h1 >= 360) {
      h1 -= 360;
    }
    t = (h1 >= 164.0) && (h1 <= 345.0) ? 0.56 + abs(0.2 * cos((PI * (h1 + 168.0)) / 180.0)) : 0.36 + abs(0.4 * cos((PI * (h1 + 35.0)) / 180.0));
    c4 = c1 * c1 * c1 * c1;
    f = sqrt(c4 / (c4 + 1900.0));
    sh = sc * (f * t + 1.0 - f);
    delL = L1 - L2;
    delC = c1 - c2;
    delA = a1 - a2;
    delB = b1 - b2;
    dH2 = delA * delA + delB * delB - delC * delC;
    v1 = delL / (L * sl);
    v2 = delC / (C * sc);
    v3 = sh;
    return sqrt(v1 * v1 + v2 * v2 + (dH2 / (v3 * v3)));
  };

  Color.prototype.get = function(modechan) {
    var channel, i, me, mode, ref, src;
    me = this;
    ref = modechan.split('.'), mode = ref[0], channel = ref[1];
    src = me[mode]();
    if (channel) {
      i = mode.indexOf(channel);
      if (i > -1) {
        return src[i];
      } else {
        return console.warn('unknown channel ' + channel + ' in mode ' + mode);
      }
    } else {
      return src;
    }
  };

  Color.prototype.set = function(modechan, value) {
    var channel, i, me, mode, ref, src;
    me = this;
    ref = modechan.split('.'), mode = ref[0], channel = ref[1];
    if (channel) {
      src = me[mode]();
      i = mode.indexOf(channel);
      if (i > -1) {
        if (type(value) === 'string') {
          switch (value.charAt(0)) {
            case '+':
              src[i] += +value;
              break;
            case '-':
              src[i] += +value;
              break;
            case '*':
              src[i] *= +(value.substr(1));
              break;
            case '/':
              src[i] /= +(value.substr(1));
              break;
            default:
              src[i] = +value;
          }
        } else {
          src[i] = value;
        }
      } else {
        console.warn('unknown channel ' + channel + ' in mode ' + mode);
      }
    } else {
      src = value;
    }
    return chroma(src, mode).alpha(me.alpha());
  };

  Color.prototype.clipped = function() {
    return this._rgb._clipped || false;
  };

  Color.prototype.alpha = function(a) {
    if (arguments.length) {
      return chroma.rgb([this._rgb[0], this._rgb[1], this._rgb[2], a]);
    }
    return this._rgb[3];
  };

  Color.prototype.darken = function(amount) {
    var lab, me;
    if (amount == null) {
      amount = 1;
    }
    me = this;
    lab = me.lab();
    lab[0] -= LAB_CONSTANTS.Kn * amount;
    return chroma.lab(lab).alpha(me.alpha());
  };

  Color.prototype.brighten = function(amount) {
    if (amount == null) {
      amount = 1;
    }
    return this.darken(-amount);
  };

  Color.prototype.darker = Color.prototype.darken;

  Color.prototype.brighter = Color.prototype.brighten;

  Color.prototype.saturate = function(amount) {
    var lch, me;
    if (amount == null) {
      amount = 1;
    }
    me = this;
    lch = me.lch();
    lch[1] += amount * LAB_CONSTANTS.Kn;
    if (lch[1] < 0) {
      lch[1] = 0;
    }
    return chroma.lch(lch).alpha(me.alpha());
  };

  Color.prototype.desaturate = function(amount) {
    if (amount == null) {
      amount = 1;
    }
    return this.saturate(-amount);
  };

  Color.prototype.premultiply = function() {
    var a, rgb;
    rgb = this.rgb();
    a = this.alpha();
    return chroma(rgb[0] * a, rgb[1] * a, rgb[2] * a, a);
  };

  blend = function(bottom, top, mode) {
    if (!blend[mode]) {
      throw 'unknown blend mode ' + mode;
    }
    return blend[mode](bottom, top);
  };

  blend_f = function(f) {
    return function(bottom, top) {
      var c0, c1;
      c0 = chroma(top).rgb();
      c1 = chroma(bottom).rgb();
      return chroma(f(c0, c1), 'rgb');
    };
  };

  each = function(f) {
    return function(c0, c1) {
      var i, o, out;
      out = [];
      for (i = o = 0; o <= 3; i = ++o) {
        out[i] = f(c0[i], c1[i]);
      }
      return out;
    };
  };

  normal = function(a, b) {
    return a;
  };

  multiply = function(a, b) {
    return a * b / 255;
  };

  darken = function(a, b) {
    if (a > b) {
      return b;
    } else {
      return a;
    }
  };

  lighten = function(a, b) {
    if (a > b) {
      return a;
    } else {
      return b;
    }
  };

  screen = function(a, b) {
    return 255 * (1 - (1 - a / 255) * (1 - b / 255));
  };

  overlay = function(a, b) {
    if (b < 128) {
      return 2 * a * b / 255;
    } else {
      return 255 * (1 - 2 * (1 - a / 255) * (1 - b / 255));
    }
  };

  burn = function(a, b) {
    return 255 * (1 - (1 - b / 255) / (a / 255));
  };

  dodge = function(a, b) {
    if (a === 255) {
      return 255;
    }
    a = 255 * (b / 255) / (1 - a / 255);
    if (a > 255) {
      return 255;
    } else {
      return a;
    }
  };

  blend.normal = blend_f(each(normal));

  blend.multiply = blend_f(each(multiply));

  blend.screen = blend_f(each(screen));

  blend.overlay = blend_f(each(overlay));

  blend.darken = blend_f(each(darken));

  blend.lighten = blend_f(each(lighten));

  blend.dodge = blend_f(each(dodge));

  blend.burn = blend_f(each(burn));

  chroma.blend = blend;

  chroma.analyze = function(data) {
    var len, o, r, val;
    r = {
      min: Number.MAX_VALUE,
      max: Number.MAX_VALUE * -1,
      sum: 0,
      values: [],
      count: 0
    };
    for (o = 0, len = data.length; o < len; o++) {
      val = data[o];
      if ((val != null) && !isNaN(val)) {
        r.values.push(val);
        r.sum += val;
        if (val < r.min) {
          r.min = val;
        }
        if (val > r.max) {
          r.max = val;
        }
        r.count += 1;
      }
    }
    r.domain = [r.min, r.max];
    r.limits = function(mode, num) {
      return chroma.limits(r, mode, num);
    };
    return r;
  };

  chroma.scale = function(colors, positions) {
    var _classes, _colorCache, _colors, _correctLightness, _domain, _fixed, _gamma, _max, _min, _mode, _nacol, _out, _padding, _pos, _spread, _useCache, classifyValue, f, getClass, getColor, resetCache, setColors, tmap;
    _mode = 'rgb';
    _nacol = chroma('#ccc');
    _spread = 0;
    _fixed = false;
    _domain = [0, 1];
    _pos = [];
    _padding = [0, 0];
    _classes = false;
    _colors = [];
    _out = false;
    _min = 0;
    _max = 1;
    _correctLightness = false;
    _colorCache = {};
    _useCache = true;
    _gamma = 1;
    setColors = function(colors) {
      var c, col, o, ref, ref1, w;
      if (colors == null) {
        colors = ['#fff', '#000'];
      }
      if ((colors != null) && type(colors) === 'string' && (chroma.brewer != null)) {
        colors = chroma.brewer[colors] || chroma.brewer[colors.toLowerCase()] || colors;
      }
      if (type(colors) === 'array') {
        if (colors.length === 1) {
          colors = [colors[0], colors[0]];
        }
        colors = colors.slice(0);
        for (c = o = 0, ref = colors.length - 1; 0 <= ref ? o <= ref : o >= ref; c = 0 <= ref ? ++o : --o) {
          col = colors[c];
          if (type(col) === "string") {
            colors[c] = chroma(col);
          }
        }
        _pos.length = 0;
        for (c = w = 0, ref1 = colors.length - 1; 0 <= ref1 ? w <= ref1 : w >= ref1; c = 0 <= ref1 ? ++w : --w) {
          _pos.push(c / (colors.length - 1));
        }
      }
      resetCache();
      return _colors = colors;
    };
    getClass = function(value) {
      var i, n;
      if (_classes != null) {
        n = _classes.length - 1;
        i = 0;
        while (i < n && value >= _classes[i]) {
          i++;
        }
        return i - 1;
      }
      return 0;
    };
    tmap = function(t) {
      return t;
    };
    classifyValue = function(value) {
      var i, maxc, minc, n, val;
      val = value;
      if (_classes.length > 2) {
        n = _classes.length - 1;
        i = getClass(value);
        minc = _classes[0] + (_classes[1] - _classes[0]) * (0 + _spread * 0.5);
        maxc = _classes[n - 1] + (_classes[n] - _classes[n - 1]) * (1 - _spread * 0.5);
        val = _min + ((_classes[i] + (_classes[i + 1] - _classes[i]) * 0.5 - minc) / (maxc - minc)) * (_max - _min);
      }
      return val;
    };
    getColor = function(val, bypassMap) {
      var c, col, i, k, o, p, ref, t;
      if (bypassMap == null) {
        bypassMap = false;
      }
      if (isNaN(val)) {
        return _nacol;
      }
      if (!bypassMap) {
        if (_classes && _classes.length > 2) {
          c = getClass(val);
          t = c / (_classes.length - 2);
        } else if (_max !== _min) {
          t = (val - _min) / (_max - _min);
        } else {
          t = 1;
        }
      } else {
        t = val;
      }
      if (!bypassMap) {
        t = tmap(t);
      }
      if (_gamma !== 1) {
        t = pow(t, _gamma);
      }
      t = _padding[0] + (t * (1 - _padding[0] - _padding[1]));
      t = Math.min(1, Math.max(0, t));
      k = Math.floor(t * 10000);
      if (_useCache && _colorCache[k]) {
        col = _colorCache[k];
      } else {
        if (type(_colors) === 'array') {
          for (i = o = 0, ref = _pos.length - 1; 0 <= ref ? o <= ref : o >= ref; i = 0 <= ref ? ++o : --o) {
            p = _pos[i];
            if (t <= p) {
              col = _colors[i];
              break;
            }
            if (t >= p && i === _pos.length - 1) {
              col = _colors[i];
              break;
            }
            if (t > p && t < _pos[i + 1]) {
              t = (t - p) / (_pos[i + 1] - p);
              col = chroma.interpolate(_colors[i], _colors[i + 1], t, _mode);
              break;
            }
          }
        } else if (type(_colors) === 'function') {
          col = _colors(t);
        }
        if (_useCache) {
          _colorCache[k] = col;
        }
      }
      return col;
    };
    resetCache = function() {
      return _colorCache = {};
    };
    setColors(colors);
    f = function(v) {
      var c;
      c = chroma(getColor(v));
      if (_out && c[_out]) {
        return c[_out]();
      } else {
        return c;
      }
    };
    f.classes = function(classes) {
      var d;
      if (classes != null) {
        if (type(classes) === 'array') {
          _classes = classes;
          _domain = [classes[0], classes[classes.length - 1]];
        } else {
          d = chroma.analyze(_domain);
          if (classes === 0) {
            _classes = [d.min, d.max];
          } else {
            _classes = chroma.limits(d, 'e', classes);
          }
        }
        return f;
      }
      return _classes;
    };
    f.domain = function(domain) {
      var c, d, k, len, o, ref, w;
      if (!arguments.length) {
        return _domain;
      }
      _min = domain[0];
      _max = domain[domain.length - 1];
      _pos = [];
      k = _colors.length;
      if (domain.length === k && _min !== _max) {
        for (o = 0, len = domain.length; o < len; o++) {
          d = domain[o];
          _pos.push((d - _min) / (_max - _min));
        }
      } else {
        for (c = w = 0, ref = k - 1; 0 <= ref ? w <= ref : w >= ref; c = 0 <= ref ? ++w : --w) {
          _pos.push(c / (k - 1));
        }
      }
      _domain = [_min, _max];
      return f;
    };
    f.mode = function(_m) {
      if (!arguments.length) {
        return _mode;
      }
      _mode = _m;
      resetCache();
      return f;
    };
    f.range = function(colors, _pos) {
      setColors(colors, _pos);
      return f;
    };
    f.out = function(_o) {
      _out = _o;
      return f;
    };
    f.spread = function(val) {
      if (!arguments.length) {
        return _spread;
      }
      _spread = val;
      return f;
    };
    f.correctLightness = function(v) {
      if (v == null) {
        v = true;
      }
      _correctLightness = v;
      resetCache();
      if (_correctLightness) {
        tmap = function(t) {
          var L0, L1, L_actual, L_diff, L_ideal, max_iter, pol, t0, t1;
          L0 = getColor(0, true).lab()[0];
          L1 = getColor(1, true).lab()[0];
          pol = L0 > L1;
          L_actual = getColor(t, true).lab()[0];
          L_ideal = L0 + (L1 - L0) * t;
          L_diff = L_actual - L_ideal;
          t0 = 0;
          t1 = 1;
          max_iter = 20;
          while (Math.abs(L_diff) > 1e-2 && max_iter-- > 0) {
            (function() {
              if (pol) {
                L_diff *= -1;
              }
              if (L_diff < 0) {
                t0 = t;
                t += (t1 - t) * 0.5;
              } else {
                t1 = t;
                t += (t0 - t) * 0.5;
              }
              L_actual = getColor(t, true).lab()[0];
              return L_diff = L_actual - L_ideal;
            })();
          }
          return t;
        };
      } else {
        tmap = function(t) {
          return t;
        };
      }
      return f;
    };
    f.padding = function(p) {
      if (p != null) {
        if (type(p) === 'number') {
          p = [p, p];
        }
        _padding = p;
        return f;
      } else {
        return _padding;
      }
    };
    f.colors = function(numColors, out) {
      var dd, dm, i, o, ref, result, results, samples, w;
      if (arguments.length < 2) {
        out = 'hex';
      }
      result = [];
      if (arguments.length === 0) {
        result = _colors.slice(0);
      } else if (numColors === 1) {
        result = [f(0.5)];
      } else if (numColors > 1) {
        dm = _domain[0];
        dd = _domain[1] - dm;
        result = (function() {
          results = [];
          for (var o = 0; 0 <= numColors ? o < numColors : o > numColors; 0 <= numColors ? o++ : o--){ results.push(o); }
          return results;
        }).apply(this).map(function(i) {
          return f(dm + i / (numColors - 1) * dd);
        });
      } else {
        colors = [];
        samples = [];
        if (_classes && _classes.length > 2) {
          for (i = w = 1, ref = _classes.length; 1 <= ref ? w < ref : w > ref; i = 1 <= ref ? ++w : --w) {
            samples.push((_classes[i - 1] + _classes[i]) * 0.5);
          }
        } else {
          samples = _domain;
        }
        result = samples.map(function(v) {
          return f(v);
        });
      }
      if (chroma[out]) {
        result = result.map(function(c) {
          return c[out]();
        });
      }
      return result;
    };
    f.cache = function(c) {
      if (c != null) {
        _useCache = c;
        return f;
      } else {
        return _useCache;
      }
    };
    f.gamma = function(g) {
      if (g != null) {
        _gamma = g;
        return f;
      } else {
        return _gamma;
      }
    };
    return f;
  };

  if (chroma.scales == null) {
    chroma.scales = {};
  }

  chroma.scales.cool = function() {
    return chroma.scale([chroma.hsl(180, 1, .9), chroma.hsl(250, .7, .4)]);
  };

  chroma.scales.hot = function() {
    return chroma.scale(['#000', '#f00', '#ff0', '#fff'], [0, .25, .75, 1]).mode('rgb');
  };

  chroma.analyze = function(data, key, filter) {
    var add, k, len, o, r, val, visit;
    r = {
      min: Number.MAX_VALUE,
      max: Number.MAX_VALUE * -1,
      sum: 0,
      values: [],
      count: 0
    };
    if (filter == null) {
      filter = function() {
        return true;
      };
    }
    add = function(val) {
      if ((val != null) && !isNaN(val)) {
        r.values.push(val);
        r.sum += val;
        if (val < r.min) {
          r.min = val;
        }
        if (val > r.max) {
          r.max = val;
        }
        r.count += 1;
      }
    };
    visit = function(val, k) {
      if (filter(val, k)) {
        if ((key != null) && type(key) === 'function') {
          return add(key(val));
        } else if ((key != null) && type(key) === 'string' || type(key) === 'number') {
          return add(val[key]);
        } else {
          return add(val);
        }
      }
    };
    if (type(data) === 'array') {
      for (o = 0, len = data.length; o < len; o++) {
        val = data[o];
        visit(val);
      }
    } else {
      for (k in data) {
        val = data[k];
        visit(val, k);
      }
    }
    r.domain = [r.min, r.max];
    r.limits = function(mode, num) {
      return chroma.limits(r, mode, num);
    };
    return r;
  };

  chroma.limits = function(data, mode, num) {
    var aa, ab, ac, ad, ae, af, ag, ah, ai, aj, ak, al, am, assignments, best, centroids, cluster, clusterSizes, dist, i, j, kClusters, limits, max_log, min, min_log, mindist, n, nb_iters, newCentroids, o, p, pb, pr, ref, ref1, ref10, ref11, ref12, ref13, ref14, ref2, ref3, ref4, ref5, ref6, ref7, ref8, ref9, repeat, sum, tmpKMeansBreaks, v, value, values, w;
    if (mode == null) {
      mode = 'equal';
    }
    if (num == null) {
      num = 7;
    }
    if (type(data) === 'array') {
      data = chroma.analyze(data);
    }
    min = data.min;
    max = data.max;
    sum = data.sum;
    values = data.values.sort(function(a, b) {
      return a - b;
    });
    if (num === 1) {
      return [min, max];
    }
    limits = [];
    if (mode.substr(0, 1) === 'c') {
      limits.push(min);
      limits.push(max);
    }
    if (mode.substr(0, 1) === 'e') {
      limits.push(min);
      for (i = o = 1, ref = num - 1; 1 <= ref ? o <= ref : o >= ref; i = 1 <= ref ? ++o : --o) {
        limits.push(min + (i / num) * (max - min));
      }
      limits.push(max);
    } else if (mode.substr(0, 1) === 'l') {
      if (min <= 0) {
        throw 'Logarithmic scales are only possible for values > 0';
      }
      min_log = Math.LOG10E * log(min);
      max_log = Math.LOG10E * log(max);
      limits.push(min);
      for (i = w = 1, ref1 = num - 1; 1 <= ref1 ? w <= ref1 : w >= ref1; i = 1 <= ref1 ? ++w : --w) {
        limits.push(pow(10, min_log + (i / num) * (max_log - min_log)));
      }
      limits.push(max);
    } else if (mode.substr(0, 1) === 'q') {
      limits.push(min);
      for (i = aa = 1, ref2 = num - 1; 1 <= ref2 ? aa <= ref2 : aa >= ref2; i = 1 <= ref2 ? ++aa : --aa) {
        p = (values.length - 1) * i / num;
        pb = floor(p);
        if (pb === p) {
          limits.push(values[pb]);
        } else {
          pr = p - pb;
          limits.push(values[pb] * (1 - pr) + values[pb + 1] * pr);
        }
      }
      limits.push(max);
    } else if (mode.substr(0, 1) === 'k') {

      /*
      implementation based on
      http://code.google.com/p/figue/source/browse/trunk/figue.js#336
      simplified for 1-d input values
       */
      n = values.length;
      assignments = new Array(n);
      clusterSizes = new Array(num);
      repeat = true;
      nb_iters = 0;
      centroids = null;
      centroids = [];
      centroids.push(min);
      for (i = ab = 1, ref3 = num - 1; 1 <= ref3 ? ab <= ref3 : ab >= ref3; i = 1 <= ref3 ? ++ab : --ab) {
        centroids.push(min + (i / num) * (max - min));
      }
      centroids.push(max);
      while (repeat) {
        for (j = ac = 0, ref4 = num - 1; 0 <= ref4 ? ac <= ref4 : ac >= ref4; j = 0 <= ref4 ? ++ac : --ac) {
          clusterSizes[j] = 0;
        }
        for (i = ad = 0, ref5 = n - 1; 0 <= ref5 ? ad <= ref5 : ad >= ref5; i = 0 <= ref5 ? ++ad : --ad) {
          value = values[i];
          mindist = Number.MAX_VALUE;
          for (j = ae = 0, ref6 = num - 1; 0 <= ref6 ? ae <= ref6 : ae >= ref6; j = 0 <= ref6 ? ++ae : --ae) {
            dist = abs(centroids[j] - value);
            if (dist < mindist) {
              mindist = dist;
              best = j;
            }
          }
          clusterSizes[best]++;
          assignments[i] = best;
        }
        newCentroids = new Array(num);
        for (j = af = 0, ref7 = num - 1; 0 <= ref7 ? af <= ref7 : af >= ref7; j = 0 <= ref7 ? ++af : --af) {
          newCentroids[j] = null;
        }
        for (i = ag = 0, ref8 = n - 1; 0 <= ref8 ? ag <= ref8 : ag >= ref8; i = 0 <= ref8 ? ++ag : --ag) {
          cluster = assignments[i];
          if (newCentroids[cluster] === null) {
            newCentroids[cluster] = values[i];
          } else {
            newCentroids[cluster] += values[i];
          }
        }
        for (j = ah = 0, ref9 = num - 1; 0 <= ref9 ? ah <= ref9 : ah >= ref9; j = 0 <= ref9 ? ++ah : --ah) {
          newCentroids[j] *= 1 / clusterSizes[j];
        }
        repeat = false;
        for (j = ai = 0, ref10 = num - 1; 0 <= ref10 ? ai <= ref10 : ai >= ref10; j = 0 <= ref10 ? ++ai : --ai) {
          if (newCentroids[j] !== centroids[i]) {
            repeat = true;
            break;
          }
        }
        centroids = newCentroids;
        nb_iters++;
        if (nb_iters > 200) {
          repeat = false;
        }
      }
      kClusters = {};
      for (j = aj = 0, ref11 = num - 1; 0 <= ref11 ? aj <= ref11 : aj >= ref11; j = 0 <= ref11 ? ++aj : --aj) {
        kClusters[j] = [];
      }
      for (i = ak = 0, ref12 = n - 1; 0 <= ref12 ? ak <= ref12 : ak >= ref12; i = 0 <= ref12 ? ++ak : --ak) {
        cluster = assignments[i];
        kClusters[cluster].push(values[i]);
      }
      tmpKMeansBreaks = [];
      for (j = al = 0, ref13 = num - 1; 0 <= ref13 ? al <= ref13 : al >= ref13; j = 0 <= ref13 ? ++al : --al) {
        tmpKMeansBreaks.push(kClusters[j][0]);
        tmpKMeansBreaks.push(kClusters[j][kClusters[j].length - 1]);
      }
      tmpKMeansBreaks = tmpKMeansBreaks.sort(function(a, b) {
        return a - b;
      });
      limits.push(tmpKMeansBreaks[0]);
      for (i = am = 1, ref14 = tmpKMeansBreaks.length - 1; am <= ref14; i = am += 2) {
        v = tmpKMeansBreaks[i];
        if (!isNaN(v) && limits.indexOf(v) === -1) {
          limits.push(v);
        }
      }
    }
    return limits;
  };

  hsi2rgb = function(h, s, i) {

    /*
    borrowed from here:
    http://hummer.stanford.edu/museinfo/doc/examples/humdrum/keyscape2/hsi2rgb.cpp
     */
    var args, b, g, r;
    args = unpack(arguments);
    h = args[0], s = args[1], i = args[2];
    if (isNaN(h)) {
      h = 0;
    }
    h /= 360;
    if (h < 1 / 3) {
      b = (1 - s) / 3;
      r = (1 + s * cos(TWOPI * h) / cos(PITHIRD - TWOPI * h)) / 3;
      g = 1 - (b + r);
    } else if (h < 2 / 3) {
      h -= 1 / 3;
      r = (1 - s) / 3;
      g = (1 + s * cos(TWOPI * h) / cos(PITHIRD - TWOPI * h)) / 3;
      b = 1 - (r + g);
    } else {
      h -= 2 / 3;
      g = (1 - s) / 3;
      b = (1 + s * cos(TWOPI * h) / cos(PITHIRD - TWOPI * h)) / 3;
      r = 1 - (g + b);
    }
    r = limit(i * r * 3);
    g = limit(i * g * 3);
    b = limit(i * b * 3);
    return [r * 255, g * 255, b * 255, args.length > 3 ? args[3] : 1];
  };

  rgb2hsi = function() {

    /*
    borrowed from here:
    http://hummer.stanford.edu/museinfo/doc/examples/humdrum/keyscape2/rgb2hsi.cpp
     */
    var b, g, h, i, min, r, ref, s;
    ref = unpack(arguments), r = ref[0], g = ref[1], b = ref[2];
    TWOPI = Math.PI * 2;
    r /= 255;
    g /= 255;
    b /= 255;
    min = Math.min(r, g, b);
    i = (r + g + b) / 3;
    s = 1 - min / i;
    if (s === 0) {
      h = 0;
    } else {
      h = ((r - g) + (r - b)) / 2;
      h /= Math.sqrt((r - g) * (r - g) + (r - b) * (g - b));
      h = Math.acos(h);
      if (b > g) {
        h = TWOPI - h;
      }
      h /= TWOPI;
    }
    return [h * 360, s, i];
  };

  chroma.hsi = function() {
    return (function(func, args, ctor) {
      ctor.prototype = func.prototype;
      var child = new ctor, result = func.apply(child, args);
      return Object(result) === result ? result : child;
    })(Color, slice.call(arguments).concat(['hsi']), function(){});
  };

  _input.hsi = hsi2rgb;

  Color.prototype.hsi = function() {
    return rgb2hsi(this._rgb);
  };

  interpolate_hsx = function(col1, col2, f, m) {
    var dh, hue, hue0, hue1, lbv, lbv0, lbv1, res, sat, sat0, sat1, xyz0, xyz1;
    if (m === 'hsl') {
      xyz0 = col1.hsl();
      xyz1 = col2.hsl();
    } else if (m === 'hsv') {
      xyz0 = col1.hsv();
      xyz1 = col2.hsv();
    } else if (m === 'hcg') {
      xyz0 = col1.hcg();
      xyz1 = col2.hcg();
    } else if (m === 'hsi') {
      xyz0 = col1.hsi();
      xyz1 = col2.hsi();
    } else if (m === 'lch' || m === 'hcl') {
      m = 'hcl';
      xyz0 = col1.hcl();
      xyz1 = col2.hcl();
    }
    if (m.substr(0, 1) === 'h') {
      hue0 = xyz0[0], sat0 = xyz0[1], lbv0 = xyz0[2];
      hue1 = xyz1[0], sat1 = xyz1[1], lbv1 = xyz1[2];
    }
    if (!isNaN(hue0) && !isNaN(hue1)) {
      if (hue1 > hue0 && hue1 - hue0 > 180) {
        dh = hue1 - (hue0 + 360);
      } else if (hue1 < hue0 && hue0 - hue1 > 180) {
        dh = hue1 + 360 - hue0;
      } else {
        dh = hue1 - hue0;
      }
      hue = hue0 + f * dh;
    } else if (!isNaN(hue0)) {
      hue = hue0;
      if ((lbv1 === 1 || lbv1 === 0) && m !== 'hsv') {
        sat = sat0;
      }
    } else if (!isNaN(hue1)) {
      hue = hue1;
      if ((lbv0 === 1 || lbv0 === 0) && m !== 'hsv') {
        sat = sat1;
      }
    } else {
      hue = Number.NaN;
    }
    if (sat == null) {
      sat = sat0 + f * (sat1 - sat0);
    }
    lbv = lbv0 + f * (lbv1 - lbv0);
    return res = chroma[m](hue, sat, lbv);
  };

  _interpolators = _interpolators.concat((function() {
    var len, o, ref, results;
    ref = ['hsv', 'hsl', 'hsi', 'hcl', 'lch', 'hcg'];
    results = [];
    for (o = 0, len = ref.length; o < len; o++) {
      m = ref[o];
      results.push([m, interpolate_hsx]);
    }
    return results;
  })());

  interpolate_num = function(col1, col2, f, m) {
    var n1, n2;
    n1 = col1.num();
    n2 = col2.num();
    return chroma.num(n1 + (n2 - n1) * f, 'num');
  };

  _interpolators.push(['num', interpolate_num]);

  interpolate_lab = function(col1, col2, f, m) {
    var res, xyz0, xyz1;
    xyz0 = col1.lab();
    xyz1 = col2.lab();
    return res = new Color(xyz0[0] + f * (xyz1[0] - xyz0[0]), xyz0[1] + f * (xyz1[1] - xyz0[1]), xyz0[2] + f * (xyz1[2] - xyz0[2]), m);
  };

  _interpolators.push(['lab', interpolate_lab]);

}).call(this);