From Code to Community: Sponsoring The Perl and Raku Conference 2025 Learn more

PJACKLAM / Math-Matrix-0.94 / t / mldiv.t 

            

              
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
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155

              
#!perl
use strict;
use warnings;
use Math::Matrix;
use Test::More tests => 12;
note('mldiv() when "denominator" is an M-by-N matrix with M = N');
{
    my $A = Math::Matrix -> new([[  2,  2, -7,  2,  2 ],
                                 [  0, -8,  4, -2,  8 ],
                                 [ -6, -6, -3,  6, -6 ],
                                 [  4, -2,  8, -4,  2 ],
                                 [ -4,  0, -1,  5, -6 ]]);
    my $y = Math::Matrix -> new([[  -38,   15, -103 ],
                                 [   62,  -72,  -10 ],
                                 [  -66,   99,   33 ],
                                 [   84,  -68,   42 ],
                                 [  -61,   71,   32 ]]);
    my $x = $y -> mldiv($A);
    is(ref($x), 'Math::Matrix', '$x is a Math::Matrix');
    is_deeply([ @$x ], [[  4, -2, -9 ],
                        [ -3, -2, -1 ],
                        [  4, -5,  7 ],
                        [ -7,  2, -9 ],
                        [  1, -8, -8 ]], '$x has the right values');
    # Verify that modifying $x does not modify $A or $y.
    my ($nrowx, $ncolx) = $x -> size();
    for my $i (0 .. $nrowx - 1) {
        for my $j (0 .. $ncolx - 1) {
            $x -> [$i][$j] += 100;
        }
    }
    is_deeply([ @$A ], [[  2,  2, -7,  2,  2 ],
                        [  0, -8,  4, -2,  8 ],
                        [ -6, -6, -3,  6, -6 ],
                        [  4, -2,  8, -4,  2 ],
                        [ -4,  0, -1,  5, -6 ]], '$A is unmodified');
    is_deeply([ @$y ], [[  -38,   15, -103 ],
                        [   62,  -72,  -10 ],
                        [  -66,   99,   33 ],
                        [   84,  -68,   42 ],
                        [  -61,   71,   32 ]], '$y is unmodified');
}
note('mldiv() when "denominator" is an M-by-N matrix with M > N');
{
    my $A = Math::Matrix -> new([[  7, -9,  5,  4 ],
                                 [  8,  1,  0,  3 ],
                                 [  4,  0,  7, -7 ],
                                 [ -5,  2,  9,  4 ],
                                 [ -2,  5,  5,  4 ]]);
    my $y = Math::Matrix -> new([[   0,  37,  37 ],
                                 [  99, -66,  23 ],
                                 [ -59,  11, -17 ],
                                 [ -24,  18,  33 ],
                                 [  40, -35,  28 ]]);
    my $x = $y -> mldiv($A);
    is(ref($x), 'Math::Matrix', '$x is a Math::Matrix');
    # Avoid tiny errors. If an element is very close to an integer, round it to
    # that integer, otherwise use the original value.
    $x = $x -> sapply(sub {
                          my $r = sprintf('%.0f', $_[0]);
                          abs($r - $_[0]) < 1e-12 ? $r : $_[0];
                      });
    is_deeply([ @$x ], [[  8, -6,  1 ],
                        [  8, -9,  0 ],
                        [ -4,  2,  2 ],
                        [  9, -3,  5 ]], '$x has the right values');
    # Verify that modifying $x does not modify $A or $y.
    my ($nrowx, $ncolx) = $x -> size();
    for my $i (0 .. $nrowx - 1) {
        for my $j (0 .. $ncolx - 1) {
            $x -> [$i][$j] += 100;
        }
    }
    is_deeply([ @$A ], [[  7, -9,  5,  4 ],
                        [  8,  1,  0,  3 ],
                        [  4,  0,  7, -7 ],
                        [ -5,  2,  9,  4 ],
                        [ -2,  5,  5,  4 ]], '$A is unmodified');
    is_deeply([ @$y ], [[   0,  37,  37 ],
                        [  99, -66,  23 ],
                        [ -59,  11, -17 ],
                        [ -24,  18,  33 ],
                        [  40, -35,  28 ]], '$y is unmodified');
}
note('mldiv() when "denominator" is an M-by-N matrix with M < N');
{
    my $A = Math::Matrix -> new([[  2, -2, -1, -2,  4 ],
                                 [ -2,  0,  0,  1,  0 ],
                                 [  0, -3,  0,  1, -2 ],
                                 [ -2, -3,  1,  1, -2 ]]);
    my $y = Math::Matrix -> new([[   5,  18,   6 ],
                                 [   3,   5,  -5 ],
                                 [ -23,   0,  -7 ],
                                 [ -14,   6, -15 ]]);
    my $x = $y -> mldiv($A);
    is(ref($x), 'Math::Matrix', '$x is a Math::Matrix');
    # Avoid negative zero in the output.
    $x = $x -> sapply(sub { $_[0] == 0 ? abs($_[0]) : $_[0] });
    is_deeply([ @$x ], [[       0,       0,       0,       0 ],
                        [  -0.125,       0,  -0.125,  -0.125 ],
                        [       0,       0,      -1,       1 ],
                        [       0,       1,       0,       0 ],
                        [  0.1875,     0.5, -0.3125,  0.1875 ]],
              '$x has the right values');
    # Verify that modifying $x does not modify $A or $y.
    my ($nrowx, $ncolx) = $x -> size();
    for my $i (0 .. $nrowx - 1) {
        for my $j (0 .. $ncolx - 1) {
            $x -> [$i][$j] += 100;
        }
    }
    is_deeply([ @$A ], [[  2, -2, -1, -2,  4 ],
                        [ -2,  0,  0,  1,  0 ],
                        [  0, -3,  0,  1, -2 ],
                        [ -2, -3,  1,  1, -2 ]], '$A is unmodified');
    is_deeply([ @$y ], [[   5,  18,   6 ],
                        [   3,   5,  -5 ],
                        [ -23,   0,  -7 ],
                        [ -14,   6, -15 ]], '$y is unmodified');
}