39 lines
1.0 KiB
JavaScript
39 lines
1.0 KiB
JavaScript
var test = require('tape');
|
|
var ss = require('../');
|
|
|
|
function rnd(x) {
|
|
return Math.round(x * 1000) / 1000;
|
|
}
|
|
|
|
test('sample variance', function(t) {
|
|
test('can get the sample variance of a six-sided die', function(t) {
|
|
t.equal(rnd(ss.sample_variance([1, 2, 3, 4, 5, 6])), 3.5);
|
|
t.end();
|
|
});
|
|
|
|
// confirmed in R
|
|
//
|
|
// > var(1:10)
|
|
// [1] 9.166667
|
|
test('can get the sample variance of numbers 1-10', function(t) {
|
|
t.equal(rnd(ss.sample_variance([1, 2, 3, 4, 5, 6, 7, 8, 9, 10])), 9.167);
|
|
t.end();
|
|
});
|
|
|
|
test('the sample variance of two numbers that are the same is 0', function(t) {
|
|
t.equal(rnd(ss.sample_variance([1, 1])), 0);
|
|
t.end();
|
|
});
|
|
|
|
test('the sample variance of one number is null', function(t) {
|
|
t.equal(ss.sample_variance([1]), null);
|
|
t.end();
|
|
});
|
|
|
|
test('the sample variance of no numbers is null', function(t) {
|
|
t.equal(ss.sample_variance([]), null);
|
|
t.end();
|
|
});
|
|
t.end();
|
|
});
|