cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
Showing results for 
Search instead for 
Did you mean: 

Bug in symbol math Prime 6

SOLVED
Highlighted
Emerald V

Bug in symbol math Prime 6

What is it!

Bug-Syn-Prime6.png

1 ACCEPTED SOLUTION

Accepted Solutions
Highlighted

Re: Bug in symbol math Prime 6

> What is it!

Its a question with a huuuuuge picture but without a worksheet 😞

 

OK, lets get serious - the bug you found is not considered a bug by PTC but rather a feature!

This feature is called "auto-labelling" and has nothing to do with old or new symbolics.

 

The "x" in the output of the symbolic evaluation are labelled "Variable" but when you typed "solve, x" this "x" gets labelled as "(-)", meaning "Automatic".

The symbol processor (both) treats them as different variables and obviously they can't find a solution for a variable which does not occur in the equation.

 

Solution is to manually label the variable you are looking for as "Variable" or change the label of the copied output of the symbolic eval as "Automatic" (which you can't do if you use is as in the following pic).

Werner_E_0-1601030600335.png

 

Its quite annoying to have to do so!

 

View solution in original post

6 REPLIES 6
Highlighted

Re: Bug in symbol math Prime 6

> What is it!

Its a question with a huuuuuge picture but without a worksheet 😞

 

OK, lets get serious - the bug you found is not considered a bug by PTC but rather a feature!

This feature is called "auto-labelling" and has nothing to do with old or new symbolics.

 

The "x" in the output of the symbolic evaluation are labelled "Variable" but when you typed "solve, x" this "x" gets labelled as "(-)", meaning "Automatic".

The symbol processor (both) treats them as different variables and obviously they can't find a solution for a variable which does not occur in the equation.

 

Solution is to manually label the variable you are looking for as "Variable" or change the label of the copied output of the symbolic eval as "Automatic" (which you can't do if you use is as in the following pic).

Werner_E_0-1601030600335.png

 

Its quite annoying to have to do so!

 

View solution in original post

Highlighted

Re: Bug in symbol math Prime 6

Pardjn - see please attach

Highlighted

Re: Bug in symbol math Prime 6

Too late 😄

See my edited answer above

Highlighted

Re: Bug in symbol math Prime 6

In Prime < 6 no same problem!

Highlighted

Re: Bug in symbol math Prime 6


@ValeryOchkov wrote:

In Prime < 6 no same problem!


Yes, I know. But is has nothing to do with the new symbolic in P6. The bug also shows up when you chose the legacy symbolic in P6.

The problem is because they have changed how their auto-labelling works, especially in connection with the symbolic evaluation.

Give the following a try in P5 and P6 and you will see:

Werner_E_0-1601058939810.png

 

That's the reason why the following symbolic "solve, x" will only work in P5 or lower.

Werner_E_1-1601059029401.png

In Prime 6 you would have to manually change the label to make it work.

 

Of course this simple example works OK in all versions if you just use "solve" without stating the variable, but this is only possible if there are no other variables.

 

Highlighted

Re: Bug in symbol math Prime 6

Addition:

It has somehow to do with the derivative (and also happens when you integrate).
The variable chosen to take the derivative wrt has its label changed to "Variable".

Try yourself and look at the labels of the output variables

Werner_E_1-1601059782813.png

 

While the labelling of the symbolic output has changed from P5 to P6, the real bug lies in the fact that Primes automatic labeling does not pass the same variables to the Symbolic if one is labeled as "Variable" and the other as "automatic" and so the symbolic treats them as completely different variables. Don't blame the symbolic - it doesn't know anything about units and also nothing about labels. Choosing the calculation option "Units/Constants in symbolic math" does not help in this case.

 

Announcements