## 70 Reputation

13 years, 136 days

## MaplePrimes Activity

### These are questions asked by vicaut

Maple 15

How is it possible to let multiple cores compute a loop faster?

For exaple:

for i = 1 to 1000 do

*computation(i)*

end do

The goal is to let a quad core cpu split the 1000 independant computations in 4 packages of 250 each to speed up the computation by the factor 4 so that core1 computes i from 1 to 250, core2 from 251 to 500 and so on, at the same time. Is this possible?

## Undocumented error with an ODE gear para...

Maple 15

I have a strange error when i try to plot an ODE with "numeric,method=gear,parameters=[...]" as options activated. After this implementation I give the parameter a value: ODE(parameters=[123]); -> works. But when I type "odeplot(ODE, [x(t),y(t)],10..20,numpoints=100);" for example, i get the errormessage:

" Error, (in dsolve/numeric/gear) Array index out of range"

But when i remove the option "method=gear", so that the ODE is solved with default runge-kutta...

## How to pointplot many lists at once?...

Maple

I have a variable number of pointplots c[1] .. c[i] and i want to plot all in a single plot.

I tried display(c[k],k=1..i); or display(c[k]\$k=1..i); but i got an error. Typing evey list like: display(c1,c2,c3,....); is not possible because i is variable. What can i do?

## Finding all roots for an ODE in a given ...

Maple

When i try to get all roots for an ODE, i try to use fsolve:

fsolve((rhs(ODE_4))(t)=0,t=10..20);

where ODE_4 is an ODE (dsolve, numeric, output=listprocedure), where i want to find the root of the 4th variable in the ODE (4 should be an index).

Then i only get the fist root after t=10 and the computation stops. What can i do to get ALL roots in the given interval?

## Plot zeros of an ODE...

Maple

I want to plot the zeros of an ODE dependent on the change of a parameter of the ODE. My idea is to make a loop where i save the zeros to the given parameter into a file, so that i get multiple files with the zeros in it, and then make a plot with the parameter as x coordinate and the zeros as y coordinates. How can i make this possible in Maple? How can i set a variable filename, for example "parameter name = value".txt?

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