2013-08-05 23:05:23 +02:00

49 lines
1.6 KiB
JavaScript

// test atan
var assert = require('assert'),
math = require('../../../src/index.js'),
approx = require('../../../tools/approx.js'),
pi = math.pi,
complex = math.complex,
matrix = math.matrix,
unit = math.unit,
atan = math.atan,
tan = math.tan;
// number
approx.equal(atan(-1) / pi, -0.25);
approx.equal(atan(-0.5) / pi, -0.147583617650433);
approx.equal(atan(0) / pi, 0);
approx.equal(atan(0.5) / pi, 0.147583617650433);
approx.equal(atan(1) / pi, 0.25);
// complex
var re = 1.409921049596575,
im = 0.229072682968539;
approx.deepEqual(atan(complex('2+3i')), complex(re, im));
approx.deepEqual(atan(complex('2-3i')), complex(re, -im));
approx.deepEqual(atan(complex('-2+3i')), complex(-re, im));
approx.deepEqual(atan(complex('-2-3i')), complex(-re, -im));
approx.deepEqual(atan(complex('i')), complex(NaN, NaN)); // TODO: should return NaN + Infi instead
approx.deepEqual(atan(complex('1')), 0.785398163397448);
approx.deepEqual(atan(complex('1+i')), complex(1.017221967897851, 0.402359478108525));
// unit
assert.throws(function () {atan(unit('45deg'))});
assert.throws(function () {atan(unit('5 celsius'))});
// string
assert.throws(function () {atan('string')});
// inverse
approx.equal(atan(tan(-1)), -1);
approx.equal(atan(tan(0)), 0);
approx.equal(atan(tan(0.1)), 0.1);
approx.equal(atan(tan(0.5)), 0.5);
approx.equal(atan(tan(2)), -1.14159265358979);
// matrix, array, range
var atan123 = [0.785398163397448, 1.107148717794090, 1.249045772398254];
approx.deepEqual(atan([1,2,3]), atan123);
approx.deepEqual(atan(math.range('1:3')), atan123);
approx.deepEqual(atan(matrix([1,2,3])), matrix(atan123));