Re: Handling branch cuts for hypergeometric function s



> Take a look at errcatch/error or catch/throw before defining anything new.

LOL. Good point.

Though this mechanism may not be doing quite what Ray and I were discussing:
it doesn't allow an exception handler, for instance, that'd ask the user if
X>0 and then allow the calculation to continue.

Upon reflection, what we need may actually be simpler than I thought.
Perhaps all we need is a function, the default definition of which does
nothing and returns TRUE, and which could be overridden by the programmer.
In pseudocode, a program that wants to ask the user if X>0 could then do
something like this:

	if (MayAskForRange(errorcode)#false) then
		... ask for range ...
	else
		... terminate or continue ...
	endif

Since the default implementation of MayAskForRange() does nothing, we have
the current (interactive) behavior. But if a programmer provides his own
version of MayAskForRange(), that function could do whatever the programmer
wants: terminate the program, do a THROW, an ASSUME, anything.

Any thoughts?


Viktor