summaryrefslogtreecommitdiff
path: root/spec/ruby/library/matrix/antisymmetric_spec.rb
blob: a0d1a5f69b796a7cf453d343236d3e771847dcf4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
require_relative '../../spec_helper'

ruby_version_is ""..."3.1" do
  require 'matrix'

  ruby_version_is "2.6" do
    describe "Matrix#antisymmetric?" do
      it "returns true for an antisymmetric Matrix" do
        Matrix[[0, -2, Complex(1, 3)], [2, 0, 5], [-Complex(1, 3), -5, 0]].antisymmetric?.should be_true
      end

      it "returns true for a 0x0 empty matrix" do
        Matrix.empty.antisymmetric?.should be_true
      end

      it "returns false for non-antisymmetric matrices" do
        [
          Matrix[[1, 2, 3], [4, 5, 6], [7, 8, 9]],
          Matrix[[1, -2, 3], [2, 0, 6], [-3, -6, 0]],  # wrong diagonal element
          Matrix[[0, 2, -3], [2, 0, 6], [-3, 6, 0]]    # only signs wrong
        ].each do |matrix|
          matrix.antisymmetric?.should be_false
        end
      end

      it "raises an error for rectangular matrices" do
        [
          Matrix[[0], [0]],
          Matrix[[0, 0]],
          Matrix.empty(0, 2),
          Matrix.empty(2, 0),
        ].each do |rectangular_matrix|
          -> {
            rectangular_matrix.antisymmetric?
          }.should raise_error(Matrix::ErrDimensionMismatch)
        end
      end
    end
  end
end