# [SciPy-user] RE : Re: odeint memoryError

Robert VERGNES robert.vergnes@yahoo...
Tue Jul 31 01:31:59 CDT 2007

```Dear Rob,

It is related with step size and accuracy. Is there some way I could know if ODEINT will crash or not ? - hence I would adapt the length of my t_vector...

an example of crashing odeint is below:

from scipy import *
from numpy import *
from scipy.integrate import *

# Equation Parameters
t_step= 1E-12
t_start=1.0172
t_end = 1.01726095276
t_interim = t_range = arange(t_start, t_end,t_step)
print 'Length of t_range: ' + str(len(t_range))
print 'Length should be around: '+ str(((t_end-t_start)/t_step))
w0 =sqrt (10)
fo = 0.075
y0_interim = [-2.20182185029, 0.0120342071085] #[Theta_dot, Theta]

def func_f3(y,t):
"""  Jacobian function """
return [ - fo*y[0]- w0**2*sin(y[1]), y[0]]

if __name__ == '__main__':
# ODE calculation
y, infodict = odeint(func_f3,y0_interim,t_interim, full_output =1)
print y
print infodict

Rob Clewley <rhc28@cornell.edu> a écrit : Robert,

are many reasons (some even mathematical) why you might be running out
of memory. You may need to adjust some algorithmic parameters such as
step size or accuracy tolerances.

-Rob

On 30/07/07, Robert VERGNES  wrote:
> Hello,
>
> when I have a time vector too thin or long (...), then odeint crash and
> returns a "MemoryError".
>
> Apart from splitting my calculation in parts is there some ways around ? ie
> like a wrapper dealing with this exception?
>
>
> Best Regards
>
> Robert
>
>
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