Shouldn't the variable A be replaced by its value 1 when 'cases' is used instead of 'if/else'?

I really don't want to play silly games with you anymore.

I asked a simple question: "Why is the value of the canvas variable A not stored in the function, when cases is involved?"

Your answer has absolutely nothing to do with my question.

I have attended another screenshot to show the consequences of not storing the value.
cases behaves, as if there where a line operator.



cases.sm (10kb) downloaded 24 time(s).

... generally, if/else is more convenient in program.

Utilities Matrix Exclude Region.sm (36kb) downloaded 21 time(s).

... ill posed code don't speak, rather crash the project.
Glance for De Boor in Samples,,, will be pleased to re-post.

The two expressions in the screenshot in my first post are evaluated symbolically.
I think I can remember that in the past when "hovering the mouse" it was was dissolved in a chain (product) of boolean expressions, without using if/else.

I suppose what it comes down to is how input variables are passed to a function defined in a plugin and when they are evaluated w.r.t. the different optimization options.

The values of a, b and q(x) are not stored in f, as you can see in the following screenshot.


And by assigning f to f they are!
And that seems to me like a kind of invisible line operator, because it behaves like one.

by--->MarB




I do not understand. The cases function works perfectly.





cases_ok.sm (5kb) downloaded 17 time(s).


Best Regards

Carlos

... for this particular integration example, it is necessary and sufficeinet
to transform the domain of if/else [ infinitesimal ...] in scalar domain.
Here, we have it already done in term of integration.

Integrate Discontinuous [Nuance].sm (14kb) downloaded 16 time(s).

So I believe I understand what is going on a little better.
I've attached the same .sm file as before only this time with break points. If you open the debugger window and step through you can see exactly what happens.
When f(x) is defined it sets f(x) equal to cases(a,x<A,b ), which is essentially the function call of cases(). But it does not further evaluate cases() or or it's input variables.
Note when g(x) is defined it will step through and evaluate the if() function and each individual input parameter (x<A,a,b ).
The cases() function within f(x) doesn't actually evaluate until it is called with f(0).
This is why, as you described earlier, if you set f(x):=f(x) you finally get the result that you want, because at this point it will finally evaluate cases(a,x<A,b ).

I'm not sure if this is a plugin issue or if this is just how SMath handles it's plugin interface.


cases_ok_alyles_with_breakpoints.sm (6kb) downloaded 19 time(s).