74 lines
2.6 KiB
JavaScript

// test sqrt
var assert = require('assert'),
approx = require('../../../tools/approx'),
error = require('../../../lib/error/index'),
mathjs = require('../../../index'),
math = mathjs();
sqrt = math.sqrt,
bignumber = math.bignumber;
describe('sqrt', function() {
it('should return the square root of a boolean', function () {
assert.equal(sqrt(true), 1);
assert.equal(sqrt(false), 0);
});
it('should return the square root of a positive number', function() {
assert.equal(sqrt(0), 0);
assert.equal(sqrt(1), 1);
assert.equal(sqrt(4), 2);
assert.equal(sqrt(9), 3);
assert.equal(sqrt(16), 4);
assert.equal(sqrt(25), 5);
});
it('should return the square root of a negative number', function() {
assert.deepEqual(sqrt(-4), math.complex(0, 2));
assert.deepEqual(sqrt(-16), math.complex(0, 4));
});
it('should return the square root of a positive bignumber', function() {
assert.deepEqual(sqrt(bignumber(0)), bignumber(0));
assert.deepEqual(sqrt(bignumber(1)), bignumber(1));
assert.deepEqual(sqrt(bignumber(4)), bignumber(2));
assert.deepEqual(sqrt(bignumber(9)), bignumber(3));
assert.deepEqual(sqrt(bignumber(16)), bignumber(4));
assert.deepEqual(sqrt(bignumber(25)), bignumber(5));
// validate whether we are really working at high precision
var bigmath = mathjs({precision: 100});
assert.deepEqual(bigmath.sqrt(bigmath.bignumber(2)), bigmath.bignumber('1.414213562373095048801688724209698078569671875376948073176679737990732478462107038850387534327641573'));
});
it('should return the square root of a negative bignumber', function() {
assert.deepEqual(sqrt(bignumber(-4)), math.complex(0, 2));
});
it('should return the square root of a complex number', function() {
assert.deepEqual(sqrt(math.complex(3, -4)), math.complex(2, -1));
});
it('should throw an error when used with a unit', function() {
assert.throws(function () {
sqrt(math.unit(5, 'km'));
});
});
it('should throw an error when used with a string', function() {
assert.throws(function () {
sqrt('a string');
});
});
it('should return the square root of each element of a matrix', function() {
assert.deepEqual(sqrt([4,9,16,25]), [2,3,4,5]);
assert.deepEqual(sqrt([[4,9],[16,25]]), [[2,3],[4,5]]);
assert.deepEqual(sqrt(math.matrix([[4,9],[16,25]])), math.matrix([[2,3],[4,5]]));
});
it('should throw an error in case of invalid number of arguments', function() {
assert.throws(function () {sqrt()}, error.ArgumentsError);
assert.throws(function () {sqrt(1, 2)}, error.ArgumentsError);
});
});