Runge-Kutta method: Difference between revisions
Rename Perl 6 -> Raku, alphabetize, minor clean-up
Thundergnat (talk | contribs) (Rename Perl 6 -> Raku, alphabetize, minor clean-up) |
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y(9.0) = 451.56245928 Error: 4.07232E-05
y(10.0) = 675.99994902 Error: 5.09833E-05</pre>
=={{header|ALGOL 68}}==
<lang ALGOL68>
Line 307 ⟶ 308:
</pre>
=={{header|C sharp|C#}}==
<lang csharp>
using System;
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y(10.0) = 675.99994902 Error = 5.098329E-05
</pre>
=={{header|FreeBASIC}}==
{{trans|BBC BASIC}}
Line 1,852 ⟶ 1,854:
''Input:'' 1/2 (h/2) - Р5, 1 (y<sub>0</sub>) - Р8 and Р7, 0 (t<sub>0</sub>) - Р6.
=={{header|Nim}}==
Line 2,176 ⟶ 2,177:
}</lang>
{{out}}▼
<pre>y( 0) = 1.000000 ± 0.000000e+00▼
y( 1) = 1.562500 ± 1.457219e-07▼
y( 2) = 3.999999 ± 9.194792e-07▼
y( 3) = 10.562497 ± 2.909562e-06▼
y( 4) = 24.999994 ± 6.234909e-06▼
y( 5) = 52.562489 ± 1.081970e-05▼
y( 6) = 99.999983 ± 1.659460e-05▼
y( 7) = 175.562476 ± 2.351773e-05▼
y( 8) = 288.999968 ± 3.156520e-05▼
y( 9) = 451.562459 ± 4.072316e-05▼
y(10) = 675.999949 ± 5.098329e-05</pre>▼
=={{header|Perl 6}}==▼
{{Works with|rakudo|2016.03}}▼
<lang perl6>sub runge-kutta(&yp) {▼
return -> \t, \y, \δt {▼
my $a = δt * yp( t, y );▼
my $b = δt * yp( t + δt/2, y + $a/2 );▼
my $c = δt * yp( t + δt/2, y + $b/2 );▼
my $d = δt * yp( t + δt, y + $c );▼
($a + 2*($b + $c) + $d) / 6;▼
}▼
}▼
constant δt = .1;▼
my &δy = runge-kutta { $^t * sqrt($^y) };▼
loop (▼
my ($t, $y) = (0, 1);▼
$t <= 10;▼
($t, $y) »+=« (δt, δy($t, $y, δt))▼
) {▼
printf "y(%2d) = %12f ± %e\n", $t, $y, abs($y - ($t**2 + 4)**2 / 16)▼
if $t %% 1;▼
}</lang>▼
{{out}}
<pre>y( 0) = 1.000000 ± 0.000000e+00
Line 2,361 ⟶ 2,326:
10 675.99994901671 5.09832902935159E-05
</pre>
=={{header|PureBasic}}==
{{trans|BBC Basic}}
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</lang>
[[File:runge-kutta.png]]
(formerly Perl 6)
▲{{Works with|rakudo|2016.03}}
▲<lang perl6>sub runge-kutta(&yp) {
▲ return -> \t, \y, \δt {
▲ my $a = δt * yp( t, y );
▲ my $b = δt * yp( t + δt/2, y + $a/2 );
▲ my $c = δt * yp( t + δt/2, y + $b/2 );
▲ my $d = δt * yp( t + δt, y + $c );
▲ ($a + 2*($b + $c) + $d) / 6;
▲ }
▲}
▲constant δt = .1;
▲my &δy = runge-kutta { $^t * sqrt($^y) };
▲loop (
▲ my ($t, $y) = (0, 1);
▲ $t <= 10;
▲ ($t, $y) »+=« (δt, δy($t, $y, δt))
▲) {
▲ printf "y(%2d) = %12f ± %e\n", $t, $y, abs($y - ($t**2 + 4)**2 / 16)
▲ if $t %% 1;
▲}</lang>
▲{{out}}
▲<pre>y( 0) = 1.000000 ± 0.000000e+00
▲y( 1) = 1.562500 ± 1.457219e-07
▲y( 2) = 3.999999 ± 9.194792e-07
▲y( 3) = 10.562497 ± 2.909562e-06
▲y( 4) = 24.999994 ± 6.234909e-06
▲y( 5) = 52.562489 ± 1.081970e-05
▲y( 6) = 99.999983 ± 1.659460e-05
▲y( 7) = 175.562476 ± 2.351773e-05
▲y( 8) = 288.999968 ± 3.156520e-05
▲y( 9) = 451.562459 ± 4.072316e-05
▲y(10) = 675.999949 ± 5.098329e-05</pre>
=={{header|REXX}}==
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