SolveODE in CAS only solves for integer x-values?

gno shared this problem 5 years ago
New

Hi,


in CAS the command

    SolveODE[f'(x,y), P]

only gives a solution if x(P) is an integer.

The same command in Algebra (via Input Bar) is able to solve if x(P) is not integer!


In this file

https://ggbm.at/791047

move point A to any non-integer x-value and the solution in CAS (dashed red line) will become undefined, whereas the Algebra solution (solid line) still exists.


Gerhard

Comments (3)

photo
1

hello

i confirm

but if you define P:=A in CAS

then solveODE[function,P] works for all P


saludos

photo
1

Thanks, fixed for next release!

photo
1

Hello,


I think this bug is not completely solved. I have just noticed, that in CAS:


SolveODE[y'' = -9.81 - y,(0, 1),(0, 0)] works fine, but

SolveODE[y'' = -9.81 - y,(0, 1.2),(0, 0)] doesn't work


Rafal

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