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
|
#!/usr/bin/perl
use strict;
use warnings;
use utf8;
use Math::Trig;
package Fourier;
my $pi = Math::Trig::pi;
sub printArray
{
my ($array) = @_;
my $n = scalar(@$array);
for (my $m = 0; $m < $n; ++$m) {
my $q = 2*$pi*$m/$n;
print "$q ".$array->[$m]->[0]." ".$array->[$m]->[1]."\n";
}
}
sub fourierTransform
{
my ($array) = @_;
my $n = scalar(@$array);
my @sq;
my $c = int($n/2);
for (my $m = 0; $m < $n; ++$m) {
my ($sumReal, $sumImag) = (0, 0);
for (my $i = 0; $i < $n; ++$i) {
my $ptr1 = $array->[$i];
for (my $c = 0; $c < $n; ++$c) {
my $ptr2 = $array->[$c];
die "$0: undefined for $i \n" if (!defined($ptr1));
die "$0: undefined for $c \n" if (!defined($ptr2));
my $value = ($i < $c) ? $array->[$i]->[$c] : $array->[$c]->[$i];
$sumReal += cos(2*$pi*($i-$c)*$m/$n)*$value;
$sumImag += sin(2*$pi*($i-$c)*$m/$n)*$value;
}
}
$sq[$m] = [$sumReal/$n, $sumImag/$n];
}
return @sq;
}
sub loadMatrix
{
my ($file, $label) = @_;
open(FILE, "<", "$file") or die "$0: Cannot open $file : $!\n";
my @m;
my $found = 0;
while (<FILE>) {
next if (/cmdline:/i);
if (/^\Q$label/) {
$found = 1;
last;
}
}
if (!$found) {
close(FILE);
die "$0: Cannot find $label in $file\n"
}
$_ = <FILE>;
chomp;
my @temp = split;
if (scalar(@temp) != 2) {
close(FILE);
die "$0: Expected 2 sizes found @temp instead\n";
}
my $rows = $temp[0];
my $cols = $temp[1];
while (<FILE>) {
chomp;
my @temp = split;
last if (scalar(@temp) != $cols);
#print @temp;
#print "\n";
push @m, \@temp;
}
close(FILE);
#print "----------\n";
my $r = scalar(@m);
if ($r != $rows) {
die "$0: Expected $rows rows but found $r instead\n";
}
print STDERR "$0: Read matrix $label from $file with $rows rows and $cols columns.\n";
return @m;
}
1;
|
