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user variables in SOLVE - Printable Version

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user variables in SOLVE - sinan oz - 04-19-2018 03:00 PM

When I use user variables in "SOLVE" application, the prime couldn't solve 3 variables 3 equations.
what could be the reason?
example: 1)Are=pi * di 2) vo=are * st* n 3) de= vo/tt

RE: user variables in SOLVE - Tim Wessman - 04-19-2018 03:08 PM

The reason is that we screwed up.

In the current version of the software, user defined variables don't play nicely in the "solve" app. It solves correctly, but when it reaches the step to store the value back into the variable by name, it incorrectly only looks for built in names and doesn't find the user created ones. Sad

You can get around this for now by either just using A-Z, or else use the ""fsolve" command on the CAS screen. "fsolve" is what the solve app uses internally.

RE: user variables in SOLVE - compsystems - 04-19-2018 04:10 PM

There is a conflict within the applications and external definitions from HOME or CAS. when defining A, B, ... X, Y, ... as 0, in some cases the results are not as expected. I think the only solution to avoid this problem is the one made by the classpad calculator, that is, to leave the variables A, B, ... X, Y, ... free, and use some alternatives A, B, ... X, in bold as user variables

[Image: image022.gif]

example of the conflict of variables

RE: user variables in SOLVE - jtucker - 04-20-2018 06:21 PM

That's funny, I am new to Prime, but user variables are working for me in my SOLVER Apps. Is this issue only for simultaneous equations?