manticore/Manticore/Num/Trig.pm
2023-12-28 13:01:16 +01:00

70 lines
1.3 KiB
Perl

package Manticore::Num::Trig;
use strict;
use warnings;
use Math::BigRat lib => 'GMP';
# Sin, cos, first terms
# 1/0! - x^2/2! + x^4/4! - x^6/6!
sub proxCos {
my ($steps, $x) = @_;
my $mxsq = -$x*$x;
my $sum = 0;
my $fa = 1;
for(1..$steps) {
my $step2 = $_ * 2;
$sum += $fa;
$fa *= $mxsq/($step2*($step2-1))
}
return $sum
}
# x/1! - x^3/3! + x^5/5! - x^7/7!
sub proxSin {
my ($steps, $x) = @_;
my $mxsq = -$x*$x;
my $sum = 0;
my $fa = $x;
for(1..$steps) {
my $step2 = $_ * 2;
$sum += $fa;
$fa *= $mxsq/($step2*($step2+1))
}
return $sum
}
# sin,cos, first terms and round by continued fractions
# 1/0! - x^2/2! + x^4/4! - x^6/6!
sub proxCosCF {
my ($steps, $x) = @_;
my $round = sub { Manticore::Num::ContinuedFraction::roundSteps($steps, $_[0]) };
my $mxsq = $round->(-$x*$x);
my $sum = 0;
my $fa = 1;
for(1..$steps) {
my $step2 = $_ * 2;
$sum = $round->($sum+$fa);
$fa = $round->($fa*$mxsq/($step2*($step2-1)))
}
return $sum
}
# x/1! - x^3/3! + x^5/5! - x^7/7!
sub proxSinCF {
my ($steps, $x) = @_;
my $round = sub { Manticore::Num::ContinuedFraction::roundSteps($steps, $_[0]) };
my $mxsq = $round->(-$x*$x);
my $sum = 0;
my $fa = $x;
for(1..$steps) {
my $step2 = $_ * 2;
$sum = $round->($sum+$fa);
$fa = $round->($fa*$mxsq/($step2*($step2+1)))
}
return $sum
}
1;