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### Solving system of ODE gets "ValueError"

I'm trying to solve a system of ODE using desolve_system but get "ValueError":

t=var('t'); f=function('f')(t); g=function('g')(t); de1 = diff(f,t) == f*sin(t); de2 = diff(g,t) == 0; desolve_system([de1, de2], [f,g])

gets:

Traceback (click to the left of this block for traceback) ... ValueError: The name "+" is not a valid Python identifier

the problem seems to be sin(t) factor, without it the system solves with no problem. Also desolve(de1, f) has no problem. What is going on here?

 2 None vdelecroix 7157 ●16 ●78 ●156 http://www.labri.fr/pe...

### Solving system of ODE gets "ValueError"

I'm trying to solve a system of ODE using desolve_system but get "ValueError":

t=var('t'); f=function('f')(t); g=function('g')(t);
de1 = diff(f,t) == f*sin(t);
de2 = diff(g,t) == 0;
desolve_system([de1, de2], [f,g])[f,g])


gets:

Traceback (click to the left of this block for traceback)
...
ValueError: The name "+" is not a valid Python identifieridentifier


the problem seems to be sin(t) factor, without it the system solves with no problem. Also desolve(de1, f) has no problem. What is going on here?

 3 retagged tmonteil 25688 ●30 ●184 ●477 http://wiki.sagemath.o...

### Solving system of ODE gets "ValueError"

I'm trying to solve a system of ODE using desolve_system but get "ValueError":

t=var('t'); f=function('f')(t); g=function('g')(t);
de1 = diff(f,t) == f*sin(t);
de2 = diff(g,t) == 0;
desolve_system([de1, de2], [f,g])


gets:

Traceback (click to the left of this block for traceback)
...
ValueError: The name "+" is not a valid Python identifier


the problem seems to be sin(t) factor, without it the system solves with no problem. Also desolve(de1, f) has no problem. What is going on here?