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incorrect symbolic integral

DS_10314450
7-Bedrock

incorrect symbolic integral

Good morning,

 

I need an integral of the function as shown below.

 

MathCAD Incorrect Integral 2025-07-10_08-55-21.png

 

This derivative of the antiderivative does not return the original function.

 

Turning to Mathmatica, here is the correct answer:

 

MathCAD Incorrect Integgral 2025-07-10_08-56-16.png

 

Ideas?

 

2 REPLIES 2
Werner_E
25-Diamond I
(To:DS_10314450)



Ideas?



Yes, please specify your question in more detail and attach your worksheet and tell us which version of Prime you are using.

 

In particular, you would have to explain why you believe that Prime's result is “incorrect”!
The quality and performance of the symbolics in Prime is far below that of Maple or Mathematica and so Prime is very often not able to deliver results or simplify them in a desirable way.

Werner_E_1-1752155774616.png

Prime seems to think that f and f2 are identical even its not capable enough to simplify f2 accordingly,

 

Let's test both functions using some random arguments:

Werner_E_0-1752157825715.png

Looks good and feeds the suspicion that Prime's integral might be correct after all, doesn't it?

Lets try using 100 000 sets of random arguments instead of just 3:

Werner_E_1-1752157969761.png

Only six times the values differ for more than 10^-5.

You have to decide if that's simply due to various numerical inaccuracies/round-off errors or if it means that Primes integral/derivative are incorrect.

Recalculation of the sheet generates different random numbers and I got up to 26 values out of 100 000 with a difference greater than 10^-5.

 

Prime 11 sheet attached

 

 

 
Werner_E
25-Diamond I
(To:Werner_E)

Just out of curiosity I gave it a try with Mathcad 15 (which uses muPad for symbolics) and it does a much better job;:

Werner_E_2-1752158885475.png

You may consider reporting the issue to official PTC support - maybe it helps to improve future versions of Prime.

 

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