Re: Constructing complex numbers using recursion

By looking at your original code and your explanation how you judge whether it is polar form, it is clear that your code is a dead loop.

Your constructComplex() calls itself unless it is not in polar form. The way you check whether it is in polar form is to see whether there is a _ in the middle of the string (not the first char). You does that PolarToRect() convertion, however the return tells us that the rect form also has a _ in it. Now your rect form seems to the computer as a polar form because of that _ in the middle... So your program just goes on and on, as it never sees an input that is not polar form based on its judgement.

Comment on Re: Constructing complex numbers using recursion

Replies are listed 'Best First'.
Re^2: Constructing complex numbers using recursion by moltar512 (Sexton) on Nov 08, 2005 at 05:50 UTC
okay.. i'm having a bit of trouble following you.. this is my reasoning... I have a polar value once i convert this to rectangular.. it is in rectangular form.. there is no _ in the rectangular form and there never will be.. therefore i thought that a _ would be a great way to see if a value is polar or rectangular (it can only be one or the other). once it is back in rectangular form, i run constructComplex again to reap the numbers from the rectangular form.. and then i want to take those numbers and pass them back to the original calling of the constructComplex method... I don't understand where you say that the _ is in the rectangular form.. It can't be and it is not when i debug via the print method please be more clear??	[reply]
Re^3: Constructing complex numbers using recursion by graff (Chancellor) on Nov 08, 2005 at 06:06 UTC
Here's a relevant quote from the OP at the start of this thread: `sub PolarToRect { my($magnitude, $angle, $real, $complex); #does it return $magnitude . " _ " $angle; }` [download] Now, can you tell us, clearly: is this subroutine supposed to return a rectangular form for a set of polar coordinates? If that's true, then the rectangular form being returned by this subroutine contains a " _ " (assuming that you fix the syntax error, which I mentioned in an earlier reply). So this is why pg is saying that this is the cause of the infinite loop -- this sub is returning rectangular coords that contain " _ ", and the constructComplex is assuming that this means the value is still in polar form. So it calls itself again (and again and again...) update: Looking at your much longer (more detailed, more confusing!) reply to Grandfather, I see that the "running" version does not have this problem with " _ " in the "PolarToRect" sub. Your original post was just very misleading.	[reply] [d/l]