mathjs/test/function/matrix/trace.test.js
2015-04-24 11:13:17 -04:00

283 lines
7.3 KiB
JavaScript

var assert = require('assert'),
approx = require('../../../tools/approx'),
math = require('../../../index');
describe('trace', function() {
it('should calculate correctly the trace of a NxN array', function() {
assert.equal(math.trace([5]), 5);
assert.equal(math.trace([[1,2],[3,4]]), 5);
approx.equal(math.trace([
[-2, 2, 3],
[-1, 1, 3],
[ 2, 0, -1]
]), -2);
approx.equal(math.trace([
[ 1, 4, 7],
[ 3, 0, 5],
[-1, 9, 11]
]), 12);
approx.equal(math.trace([
[1,7,4,3,7],
[0,7,0,3,7],
[0,7,4,3,0],
[1,7,5,9,7],
[2,7,4,3,7]
]), 28);
});
it('should calculate correctly the trace of a NxN matrix', function() {
assert.equal(math.trace(math.matrix([5])), 5);
assert.equal(math.trace(math.matrix([[1,2],[3,4]])), 5);
assert.equal(math.trace(math.matrix([[1,2],[3,4]])), 5);
approx.equal(
math.trace(
math.matrix(
[
[-2, 2, 3],
[-1, 1, 3],
[ 2, 0, -1]
])),
-2);
approx.equal(
math.trace(
math.matrix(
[
[ 1, 4, 7],
[ 3, 0, 5],
[-1, 9, 11]
])),
12);
approx.equal(
math.trace(
math.matrix(
[
[1, 7, 4, 3, 7],
[0, 7, 0, 3, 7],
[0, 7, 4, 3, 0],
[1, 7, 5, 9, 7],
[2, 7, 4, 3, 7]
])),
28);
approx.equal(math.trace(math.diag([4, -5, 6])), 5);
});
it('should calculate correctly the trace of a NxN matrix, sparse', function() {
assert.equal(math.trace(math.matrix([5], 'sparse')), 5);
assert.equal(math.trace(math.matrix([[1,2],[3,4]], 'sparse')), 5);
assert.equal(math.trace(math.matrix([[1,2],[3,4]], 'sparse')), 5);
approx.equal(
math.trace(
math.matrix(
[
[-2, 2, 3],
[-1, 1, 3],
[ 2, 0, -1]
],
'sparse')),
-2);
approx.equal(
math.trace(
math.matrix(
[
[ 1, 4, 7],
[ 3, 0, 5],
[-1, 9, 11]
],
'sparse')),
12);
approx.equal(
math.trace(
math.matrix(
[
[1, 7, 4, 3, 7],
[0, 7, 0, 3, 7],
[0, 7, 4, 3, 0],
[1, 7, 5, 9, 7],
[2, 7, 4, 3, 7]
],
'sparse')),
28);
});
it('should return N for the identity matrix',function() {
assert.equal(math.trace(math.eye(7)), 7);
assert.equal(math.trace(math.eye(2)), 2);
assert.equal(math.trace(math.eye(1)), 1);
});
it('should calculate the trace for a scalar',function() {
assert.equal(math.trace(7), 7);
var c1 = math.complex(2, 3);
var c2 = math.trace(c1);
assert.deepEqual(c1, c2);
// c2 should be a clone
c1.re = 0;
assert.equal(c1.re, 0);
assert.equal(c2.re, 2);
});
it('should calculate the trace for a 1x1 array',function() {
var c1 = math.complex(2, 3);
var c2 = math.trace([[c1]]);
assert.deepEqual(c1, c2);
// c2 should be a clone
c1.re = 0;
assert.equal(c1.re, 0);
assert.equal(c2.re, 2);
});
it('should calculate the trace for a 1x1 matrix',function() {
var c1 = math.complex(2, 3);
var c2 = math.trace(math.matrix([[c1]]));
assert.deepEqual(c1, c2);
// c2 should be a clone
c1.re = 0;
assert.equal(c1.re, 0);
assert.equal(c2.re, 2);
});
it('should calculate the trace for a 1x1 matrix, sparse',function() {
var c1 = math.complex(2, 3);
var c2 = math.trace(math.matrix([[c1]], 'sparse'));
assert.deepEqual(c1, c2);
// c2 should be a clone
c1.re = 0;
assert.equal(c1.re, 0);
assert.equal(c2.re, 2);
});
it('should calculate correctly the trace of a matrix with bignumbers', function() {
var bignumber = math.bignumber;
// 1x1
assert.deepEqual(math.trace([bignumber(5)]), bignumber(5));
// 2x2
assert.deepEqual(math.trace([
[bignumber(1), bignumber(2)],
[bignumber(3), bignumber(4)]
]), bignumber(5));
// 3x3
assert.deepEqual(math.trace([
[bignumber(-2), bignumber(2), bignumber( 3)],
[bignumber(-1), bignumber(1), bignumber( 3)],
[bignumber( 2), bignumber(0), bignumber(-1)]
]), bignumber(-2));
// the following would fail with regular Numbers due to a precision overflow
assert.deepEqual(math.trace([
[bignumber(1e10+1), bignumber(1e10)],
[bignumber(1e10), bignumber(-1e10)]
]), bignumber(1));
});
it('should calculate the trace of a matrix with mixed numbers and bignumbers', function() {
var bignumber = math.bignumber;
assert.deepEqual(math.trace([
[bignumber(2), 1],
[bignumber(3), 4]
]), bignumber(6));
});
it('should not change the value of the initial matrix', function() {
var m_test = [[1,2,3],[4,5,6],[7,8,9]];
math.trace(m_test);
assert.deepEqual(m_test, [[1,2,3],[4,5,6],[7,8,9]]);
});
it('should not accept a non-square matrix', function() {
assert.throws(function() { math.trace([1,2]); });
assert.throws(function() { math.trace([[1,2,3],[1,2,3]]); });
assert.throws(function() { math.trace([0,1],[0,1],[0,1]); });
assert.throws(function() { math.trace(math.matrix([[1,2,3],[1,2,3]])); });
assert.throws(function() { math.trace(math.matrix([[1,2,3],[1,2,3]], 'sparse')); });
});
it('should not accept arrays with dimensions higher than 2', function() {
assert.throws(function() { math.trace([[[1]]]); }, RangeError);
assert.throws(function() { math.trace(math.matrix([[[1]]])); }, RangeError);
});
it('should LaTeX trace', function () {
var expression = math.parse('trace([[1,2],[3,4]])');
assert.equal(expression.toTex(), '\\mathrm{tr}\\left(\\begin{bmatrix}1&2\\\\3&4\\\\\\end{bmatrix}\\right)');
});
describe('DenseMatrix', function () {
it('should calculate trace on a square matrix', function() {
var m = math.matrix([
[1, 2],
[4, -2]
]);
assert.equal(math.trace(m), -1);
m = math.matrix([
[0, 0, 0, 0],
[0, 0, 0, 0],
[0, 0, 0, 0],
[0, 0, 0, 0]
]);
assert.equal(math.trace(m), 0);
m = math.matrix([
[1, 0, 0, 0],
[0, 0, 2, 0],
[1, 0, 0, 0],
[0, 0, 1, 9]
]);
assert.equal(math.trace(m), 10);
});
it('should throw an error for invalid matrix', function() {
var m = math.matrix([
[1, 2, 3],
[4, 5, 6]
]);
assert.throws(function () { math.trace(m); });
});
});
describe('SparseMatrix', function () {
it('should calculate trace on a square matrix', function() {
var m = math.matrix([
[1, 2],
[4, -2]
], 'sparse');
assert.equal(math.trace(m), -1);
m = math.matrix([
[0, 0, 0, 0],
[0, 0, 0, 0],
[0, 0, 0, 0],
[0, 0, 0, 0]
], 'sparse');
assert.equal(math.trace(m), 0);
m = math.matrix([
[1, 0, 0, 0],
[0, 0, 2, 0],
[1, 0, 0, 0],
[0, 0, 1, 9]
], 'sparse');
assert.equal(math.trace(m), 10);
});
it('should throw an error for invalid matrix', function() {
var m = math.matrix([
[1, 2, 3],
[4, 5, 6]
], 'sparse');
assert.throws(function () { math.trace(m); });
});
});
});