Runge-Kutta method: Difference between revisions
move Octave section to restore alphabetic order
(incomplete octave entry) |
(move Octave section to restore alphabetic order) |
||
Line 585:
t = 9.000000, y = 451.562459, err = 4.07232e-05
t = 10.000000, y = 675.999949, err = 5.09833e-05</pre>
=={{header|Octave}}==▼
{{incomplete}}▼
Implementing Runge-Kutta in octave is a bit of a hassle. For now we'll showcase how to solve an ordinary differential equation using the lsode function.▼
<lang octave>function ydot = f(y, t)▼
ydot = t * sqrt( y );▼
endfunction▼
t = [0:10]';▼
y = lsode("f", 1, t);▼
[ t, y, y - 1/16 * (t.**2 + 4).**2 ]</lang>▼
{{out}}▼
<pre>ans =▼
0.00000 1.00000 0.00000▼
1.00000 1.56250 0.00000▼
2.00000 4.00000 0.00000▼
3.00000 10.56250 0.00000▼
4.00000 25.00000 0.00000▼
5.00000 52.56250 0.00000▼
6.00000 100.00000 0.00000▼
7.00000 175.56250 0.00000▼
8.00000 289.00001 0.00001▼
9.00000 451.56251 0.00001▼
10.00000 676.00001 0.00001</pre>▼
=={{header|PARI/GP}}==
Line 696 ⟶ 723:
y( 9) = 451.562459 ± 4.072316e-05
y(10) = 675.999949 ± 5.098329e-05</pre>
▲=={{header|Octave}}==
▲{{incomplete}}
▲Implementing Runge-Kutta in octave is a bit of a hassle. For now we'll showcase how to solve an ordinary differential equation using the lsode function.
▲<lang octave>function ydot = f(y, t)
▲ ydot = t * sqrt( y );
▲endfunction
▲t = [0:10]';
▲y = lsode("f", 1, t);
▲[ t, y, y - 1/16 * (t.**2 + 4).**2 ]</lang>
▲{{out}}
▲<pre>ans =
▲ 0.00000 1.00000 0.00000
▲ 1.00000 1.56250 0.00000
▲ 2.00000 4.00000 0.00000
▲ 3.00000 10.56250 0.00000
▲ 4.00000 25.00000 0.00000
▲ 5.00000 52.56250 0.00000
▲ 6.00000 100.00000 0.00000
▲ 7.00000 175.56250 0.00000
▲ 8.00000 289.00001 0.00001
▲ 9.00000 451.56251 0.00001
▲ 10.00000 676.00001 0.00001</pre>
=={{header|Python}}==
| |||