This post is an outgrowth of a previous post on XY-PLOTS. I should have started a new question, so here it is.

In the attached sm file, there are three definitions of the same function:
1. Using Boolean math
2. Using an if...else form
3. Using a slightly different if...else form.

They all plot the same; however, when integrating these functions, only the Boolean version works.
You can enable and disable the three forms to see that only the Boolean form works in the integral.

Runtime = 3-4 seconds for the working Boolean form. The non-working versions are instantaneous.

Is this a know problem in SMATH, or am I just missing something? Maybe it's a feature.

Thanks for any enlightenment.

FUNCTION INTEGRATION PROBLEMS.sm (23 KiB) downloaded 38 time(s).

Simplified version of the document.

FUNCTION INTEGRATION PROBLEMS (uni).sm (18 KiB) downloaded 31 time(s).

This method is also possible, but does not solve the problems with integration.

Wrote

...
Is this a know problem in SMATH, or am I just missing something? Maybe it's a feature. ...

Yes, it's a known issue, but not just in SMath, except that in other languages there are tools to handle 'piecewise continuous' functions. In maple, for example, you have the piecewise function, similar to SMath's cases, but also the much more powerful Heaviside, which is actually not a function, but a distribution (and not in the sense of probabilities, but as limit of sequences of functions)



To help understand more or less why some functions can be integrated and others can't, or be used for solve or roots, they are only candidates if the Unknowns function does not return an error and can detect its variables.


FUNCTION INTEGRATION PROBLEMS (uni) with Unknowns.sm (20 KiB) downloaded 37 time(s).

Best regards.
Alvaro.

Thank guys. I keep getting caught with my ingrained MATHCAD experience.

Moderator,
Sorry for the all caps. Mea Culpa. It was unintentional.

I suspect using 'if' function within Q(z) will not work for similar reason it did not work in these examples: https://en.smath.com/forum/yaf_postsm81767_Issues-with-cases-if-and-error.aspx#post81767