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19-Tanzanite
June 14, 2024
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A function or a variable name is required when I define derivative as a function of all 3 variables

  • June 14, 2024
  • 2 replies
  • 5082 views

Hi,

Why I cannot do like f2(x,y,z) as we can see the derivative result is depending on all 3 variables x, y, and z? Should be like that for f2? Prime 10

Cornel_0-1718372243011.png

Best answer by Werner_E

I would confirm that you found a BUG in Prime 10.

 

My first guess was that it may be due to wrong labelling of the variables/arguments, but this seems not to be the case here.

The work around using the symbolic evaluation should not be necessary.

 

The bug seems to concern only functions with more than two arguments, using a function with just two arguments works as it should.

Werner_E_0-1718375823779.png

 

Here is another workaround not needing the symbolics. A local assignment does the trick!

Werner_E_1-1718376071644.png

 

Nonetheless its a BUG which should be fixed!

 

2 replies

Cornel19-TanzaniteAuthor
19-Tanzanite
June 14, 2024

I think this is perhaps another bug coming along with Prime 10 as in Prime 9 is ok:

 

Cornel_0-1718372176173.png

 

Cornel19-TanzaniteAuthor
19-Tanzanite
June 14, 2024

Any workaround for Prime 10 to solve this?

Cornel19-TanzaniteAuthor
19-Tanzanite
June 14, 2024

I think I found a way by evaluating the expression further, but I am waiting for others opinions if the above behaviour it should be like that in Prime 10:

Cornel_0-1718372800679.png

 

Werner_E25-Diamond IAnswer
25-Diamond I
June 14, 2024

I would confirm that you found a BUG in Prime 10.

 

My first guess was that it may be due to wrong labelling of the variables/arguments, but this seems not to be the case here.

The work around using the symbolic evaluation should not be necessary.

 

The bug seems to concern only functions with more than two arguments, using a function with just two arguments works as it should.

Werner_E_0-1718375823779.png

 

Here is another workaround not needing the symbolics. A local assignment does the trick!

Werner_E_1-1718376071644.png

 

Nonetheless its a BUG which should be fixed!

 

25-Diamond I
June 14, 2024

Here some other workarounds.

Crazy! As long as any local assignment is involved, Prime seems to be happy 😉

Werner_E_0-1718376624902.png

 

 

Werner_E_1-1718376644042.png

 

But an assignment seems to be mandatory

Werner_E_2-1718376744253.png

 

 

Cornel19-TanzaniteAuthor
19-Tanzanite
June 14, 2024

@Werner_E wrote:

Nonetheless its a BUG which should be fixed!


@DJNewman...maybe the product team can take into consideration this.