# mlab.rk4

hi everyone,
I’m trying to solve a lineal differential equation system, and I,m proving with the mlab.rk4 function.
The problem I’ve found is that if the solution if a complex number, I can’t use this functin, because it doesn’t accept complex number, and I can only get the real case.

Have anyone treat with this problem?
What do you use to solve differential equation systems?

rk4 was something I wrote long ago to have a simple ODE integrator in
case scipy wasn't installed on my system. You should be using the
scipy.integrate tools

···

On 4/27/07, darkside <in.the.darkside@...287...> wrote:

hi everyone,
I'm trying to solve a lineal differential equation system, and I,m proving
with the mlab.rk4 function.
The problem I've found is that if the solution if a complex number, I can't
use this functin, because it doesn't accept complex number, and I can only
get the real case.

Have anyone treat with this problem?
What do you use to solve differential equation systems?

2007/4/27, John Hunter <jdh2358@…287…>:

···

On 4/27/07, darkside <in.the.darkside@…287…> wrote:

hi everyone,
I’m trying to solve a lineal differential equation system, and I,m proving
with the mlab.rk4 function.
The problem I’ve found is that if the solution if a complex number, I can’t
use this functin, because it doesn’t accept complex number, and I can only
get the real case.

Have anyone treat with this problem?
What do you use to solve differential equation systems?

rk4 was something I wrote long ago to have a simple ODE integrator in
case scipy wasn’t installed on my system. You should be using the

scipy.integrate tools

Thank you very much!!!

I used scipy.integrate tools, splitting complex and real part of the equations, and it worked so good!!

I tried to use: In addition I have filed a ticket for a complex ODE solver.

http://projects.scipy.org/scipy/scipy/ticket/334

But I haven’t been able to compile it. It returns a lot of errors when I tried. I suposse that it’s because of the fortran compiler, but I don’t know.

Please remove the lines in zvdemo beginning with line 121.
Rename zvdemo

mv zvdemo zvdemo.f

1. g77 -c zvdemo.f zvode.f
2. g77 -o test zvdemo.o zvode.o
3. ./test > test.out

HTH
Nils

···

On Fri, 27 Apr 2007 23:22:04 +0100 darkside <in.the.darkside@...287...> wrote:

2007/4/27, John Hunter <jdh2358@...287...>:

On 4/27/07, darkside <in.the.darkside@...287...> wrote:
> hi everyone,
> I'm trying to solve a lineal differential equation system, and I,m
proving
> with the mlab.rk4 function.
> The problem I've found is that if the solution if a complex number, I
can't
> use this functin, because it doesn't accept complex number, and I can
only
> get the real case.
>
> Have anyone treat with this problem?
> What do you use to solve differential equation systems?

rk4 was something I wrote long ago to have a simple ODE integrator in
case scipy wasn't installed on my system. You should be using the
scipy.integrate tools

Thank you very much!!!

I used scipy.integrate tools, splitting complex and real part of the
equations, and it worked so good!!

I tried to use: In addition I have filed a ticket for a complex ODE solver.
http://projects.scipy.org/scipy/scipy/ticket/334

But I haven't been able to compile it. It returns a lot of errors when I
tried. I suposse that it's because of the fortran compiler, but I don't
know.