documentation of implementation of funtions

[Joop]

Dear Mathcad users,

I would like to have a more detailed description of the math behind the functions. For example today I was looking into the cross correlation functions crosscorr(S, K, [BC], [OV]). I would like to see the expressions that are used to calculate the results. Is there any place I can find this?

regards,

Joop

[Werner_E]

The algorithms are, to my knowledge, nowhere disclosed. As far as I know, many algorithms stem from the Numerical Recipes or are at least based upon them.

http://numerical.recipes/

No sure, of course, if this also affects "crosscorr" which, as far as I am aware, was introduced just with Prime.

[Joop]

thanks for the reply. In the end I do not need the numerical algorithm but to use a function like crosscorr I must know what Math it does. What equations are solved?

Joop

[Werner_E]

Documentation sure was much better in older Mathcad versions, especially up to and including MC11.

Beginning with Prime the only "documentation" is the help system and as crosscorr is a newly introduced function all we have is the help

https://support.ptc.com/help/mathcad/r6.0/en/index.html#page/PTC_Mathcad_Help%2Fconvolution_and_cross_correlation.html%23

[Joop]

Hi Werner,

that I had found but it does not explain what the function does. How can they think that we can use a function without having info on the math?

regards,

Joop

[-MFra-]

Hi,

You can find something about the correlation of signals in Mathcad's E-Book "Signal Processing" 15.

[Joop]

Thanks again for your answer. Is this E-book public available?

For me this is not the answer I am looking for. I could guess that these are the equations that are solved. But maybe something different is done. I should be sure about the math that is solved and need a reference that states that exactly this equation is solved.

Joop

[LucMeekes]

"How can they think that we can use a function without having info on the math?"

While I think it's a good idea to provide info on the method used for each particular function, and much of this info was available for Mathcad 11 and earlier, you may be asking too much. In some cases the actual implementation may be considered confidential IP...

Also: How much info does MS provide on functions of Excel? And can you use Excel?

If you need to be absolutely certain about the way a mathematical function is implemented, you'll have to write it yourself... And prove that it functions correctly in each and every use you make of it.

Luc