toolkit/javascript/d3/test/scale/quantize-test.js
changeset 47 c0b4a8b5a012
equal deleted inserted replaced
46:efd9c589177a 47:c0b4a8b5a012
       
     1 require("../env");
       
     2 require("../../d3");
       
     3 
       
     4 var vows = require("vows"),
       
     5     assert = require("assert");
       
     6 
       
     7 var suite = vows.describe("d3.scale.quantize");
       
     8 
       
     9 suite.addBatch({
       
    10   "quantize": {
       
    11     topic: function() {
       
    12       return d3.scale.quantize;
       
    13     },
       
    14     "has the default domain [0, 1]": function(quantize) {
       
    15       var x = quantize();
       
    16       assert.deepEqual(x.domain(), [0, 1]);
       
    17       assert.equal(x(.25), 0);
       
    18     },
       
    19     "has the default range [0, 1]": function(quantize) {
       
    20       var x = quantize();
       
    21       assert.deepEqual(x.range(), [0, 1]);
       
    22       assert.equal(x(.75), 1);
       
    23     },
       
    24     "maps a number to a discrete value in the range": function(quantize) {
       
    25       var x = quantize().range([0, 1, 2]);
       
    26       assert.equal(x(0), 0);
       
    27       assert.equal(x(.2), 0);
       
    28       assert.equal(x(.4), 1);
       
    29       assert.equal(x(.6), 1);
       
    30       assert.equal(x(.8), 2);
       
    31       assert.equal(x(1), 2);
       
    32     },
       
    33     "coerces domain to numbers": function(quantize) {
       
    34       var x = quantize().domain(["0", "100"]);
       
    35       assert.strictEqual(x.domain()[0], 0);
       
    36       assert.strictEqual(x.domain()[1], 100);
       
    37     },
       
    38     "only considers the extent of the domain": function(quantize) {
       
    39       var x = quantize().domain([-1, 0, 100]);
       
    40       assert.deepEqual(x.domain(), [-1, 100]);
       
    41     },
       
    42     "clamps input values to the domain": function(quantize) {
       
    43       var a = {}, b = {}, c = {}, x = quantize().range([a, b, c]);
       
    44       assert.equal(x(-.5), a);
       
    45       assert.equal(x(1.5), c);
       
    46     },
       
    47     "range cardinality determines the degree of quantization": function(quantize) {
       
    48       var x = quantize();
       
    49       assert.inDelta(x.range(d3.range(0, 1.001, .001))(1/3), .333, 1e-6);
       
    50       assert.inDelta(x.range(d3.range(0, 1.01, .01))(1/3), .33, 1e-6);
       
    51       assert.inDelta(x.range(d3.range(0, 1.1, .1))(1/3), .3, 1e-6);
       
    52       assert.inDelta(x.range(d3.range(0, 1.2, .2))(1/3), .4, 1e-6);
       
    53       assert.inDelta(x.range(d3.range(0, 1.25, .25))(1/3), .25, 1e-6);
       
    54       assert.inDelta(x.range(d3.range(0, 1.5, .5))(1/3), .5, 1e-6);
       
    55       assert.inDelta(x.range(d3.range(1))(1/3), 0, 1e-6);
       
    56     },
       
    57     "range values are arbitrary": function(quantize) {
       
    58       var a = {}, b = {}, c = {}, x = quantize().range([a, b, c]);
       
    59       assert.equal(x(0), a);
       
    60       assert.equal(x(.2), a);
       
    61       assert.equal(x(.4), b);
       
    62       assert.equal(x(.6), b);
       
    63       assert.equal(x(.8), c);
       
    64       assert.equal(x(1), c);
       
    65     }
       
    66   }
       
    67 });
       
    68 
       
    69 suite.export(module);