| <!DOCTYPE html> |
| <!-- |
| Copyright (c) 2014 The Chromium Authors. All rights reserved. |
| Use of this source code is governed by a BSD-style license that can be |
| found in the LICENSE file. |
| --> |
| <link rel="import" href="/base/statistics.html"> |
| <script> |
| 'use strict'; |
| |
| tr.b.unittest.testSuite(function() { |
| var Statistics = tr.b.Statistics; |
| |
| test('sumBasic', function() { |
| assert.equal(Statistics.sum([1, 2, 3]), 6); |
| }); |
| |
| test('sumWithFunctor', function() { |
| var ctx = {}; |
| var ary = [1, 2, 3]; |
| assert.equal(12, Statistics.sum(ary, function(x, i) { |
| assert.equal(this, ctx); |
| assert.equal(ary[i], x); |
| return x * 2; |
| }, ctx)); |
| }); |
| |
| test('minMaxWithFunctor', function() { |
| var ctx = {}; |
| var ary = [1, 2, 3]; |
| function func(x, i) { |
| assert.equal(this, ctx); |
| assert.equal(ary[i], x); |
| return x; |
| } |
| assert.equal(Statistics.max(ary, func, ctx), 3); |
| assert.equal(Statistics.min(ary, func, ctx), 1); |
| |
| var range = Statistics.range(ary, func, ctx); |
| assert.isFalse(range.isEmpty); |
| assert.equal(range.min, 1); |
| assert.equal(range.max, 3); |
| }); |
| |
| test('maxExtrema', function() { |
| assert.equal(Statistics.max([]), -Infinity); |
| assert.equal(Statistics.min([]), Infinity); |
| }); |
| |
| test('meanBasic', function() { |
| assert.equal(Statistics.mean([1, 2, 3]), 2); |
| }); |
| |
| test('varianceBasic', function() { |
| // In [2, 4, 4, 2], all items have a deviation of 1.0 from the mean so the |
| // population variance is 4.0 / 4 = 1.0, but the sample variance is 4.0 / 3. |
| assert.equal(Statistics.variance([2, 4, 4, 2]), 4.0 / 3); |
| |
| // In [1, 2, 3], the squared deviations are 1.0, 0.0 and 1.0 respectively; |
| // population variance 2.0 / 3 but sample variance is 2.0 / 2 = 1.0. |
| assert.equal(Statistics.variance([1, 2, 3]), 1.0); |
| }); |
| |
| test('varianceWithFunctor', function() { |
| var ctx = {}; |
| var ary = [{x: 2}, |
| {x: 4}, |
| {x: 4}, |
| {x: 2}]; |
| assert.equal(4.0 / 3, Statistics.variance(ary, function(d) { |
| assert.equal(ctx, this); |
| return d.x; |
| }, ctx)); |
| }); |
| |
| test('stddevBasic', function() { |
| assert.equal(Statistics.stddev([2, 4, 4, 2]), Math.sqrt(4.0 / 3)); |
| }); |
| |
| test('stddevWithFunctor', function() { |
| var ctx = {}; |
| var ary = [{x: 2}, |
| {x: 4}, |
| {x: 4}, |
| {x: 2}]; |
| assert.equal(Math.sqrt(4.0 / 3), Statistics.stddev(ary, function(d) { |
| assert.equal(ctx, this); |
| return d.x; |
| }, ctx)); |
| }); |
| |
| test('percentile', function() { |
| var ctx = {}; |
| var ary = [{x: 0}, |
| {x: 1}, |
| {x: 2}, |
| {x: 3}, |
| {x: 4}, |
| {x: 5}, |
| {x: 6}, |
| {x: 7}, |
| {x: 8}, |
| {x: 9}]; |
| function func(d, i) { |
| assert.equal(ctx, this); |
| return d.x; |
| } |
| assert.equal(Statistics.percentile(ary, 0, func, ctx), 0); |
| assert.equal(Statistics.percentile(ary, .5, func, ctx), 4); |
| assert.equal(Statistics.percentile(ary, .75, func, ctx), 6); |
| assert.equal(Statistics.percentile(ary, 1, func, ctx), 9); |
| }); |
| |
| }); |
| </script> |
