# differential equation problems.

I am trying to get the differential equation examples to work:

x = var('x') y = function('y',x) desolve(diff(y,x) + y - 1, y)

or

t = var('t') x = function('x',t) DE = diff(x, t) + x - 1 desolve(DE, [x,t])

Both return errors. What am I doing wrong?

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Surprising! I copy pasted both the equations and they work fine for me.

Sort by » oldest newest most voted You may not be doing anything wrong. I got two different kinds of errors:

TypeError: Error executing code in Maxima
CODE:
sage99 : ('y(x))+(diff('y(x), x, 1))+(-1)$Maxima ERROR: sage99 : ('y(x))+(diff('y(x), x, 1))+(-1)$

stdin:7094:Incorrect syntax: Too many )'s
(%i87)
stdin:7145:Incorrect syntax: Premature termination of input at \$.
(%i88)


and

sage: desolve(diff(y,x) + y - 1, y)
sage103


sage: desolve(diff(y,x) + y - 1, y)
(c + e^x)*e^(-x)


Then I did it from a restart and everything worked the first time, and I can't reproduce the errors anymore. Looks like the maxima interface can get itself into a state, whether because of something I'd done previously or not. But this definitely shouldn't happen: were these the same kinds of errors you saw?

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I had to restart and it is working now for both examples. Unfortunately I did not capture the error information. If I see it again I will capture the information and post it.

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