49 lines
1.7 KiB
JavaScript
49 lines
1.7 KiB
JavaScript
var test = require('tape');
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var ss = require('../');
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test('sample skewness', function(t) {
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test('the skewness of an empty sample is null', function(t) {
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var data = [];
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t.equal(ss.sample_skewness(data), null);
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t.end();
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});
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test('the skewness of an sample with one number is null', function(t) {
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var data = [1];
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t.equal(ss.sample_skewness(data), null);
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t.end();
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});
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test('the skewness of an sample with two numbers is null', function(t) {
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var data = [1, 2];
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t.equal(ss.sample_skewness(data), null);
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t.end();
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});
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test('can calculate the skewness of SAS example 1', function(t) {
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// Data and answer taken from SKEWNESS function documentation at
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// http://support.sas.com/documentation/c../lrdict/64316/HTML/default/viewer.htm#a000245947.htm
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var data = [0, 1, 1];
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t.equal(+ss.sample_skewness(data).toPrecision(10), -1.732050808);
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t.end();
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});
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test('can calculate the skewness of SAS example 2', function(t) {
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// Data and answer taken from SKEWNESS function documentation at
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// http://support.sas.com/documentation/c../lrdict/64316/HTML/default/viewer.htm#a000245947.htm
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var data = [2, 4, 6, 3, 1];
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t.equal(+ss.sample_skewness(data).toPrecision(10), 0.5901286564);
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t.end();
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});
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test('can calculate the skewness of SAS example 3', function(t) {
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// Data and answer taken from SKEWNESS function documentation at
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// http://support.sas.com/documentation/c../lrdict/64316/HTML/default/viewer.htm#a000245947.htm
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var data = [2, 0, 0];
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t.equal(+ss.sample_skewness(data).toPrecision(10), 1.732050808);
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t.end();
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});
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t.end();
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});
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