If you are not already using floating point in your program, using it now is
likely to increase your code size a lot.  If you have it, maybe that is okay.
But this is why C gets a "bad rap" over assembly.  It is usually important to
consider the result of your C statements before accepting a quick solution.  I
suggest "rolling your own" function in C to handle the overflow/underflow that
results from integer math.

David
david@KosmosIsland.com

On Fri, 22 Feb 2002 10:29:35 -0600
Rich Mcelroy <rmcelroy@CSTSURVEY.COM> wrote:

> A is a signed long, and B is an unsigned long.  two large values.
>
> -----Original Message-----
> From: Peter Onion [mailto:ponion@SRD.BT.CO.UK]
> Sent: Friday, February 22, 2002 10:04 AM
> To: PICLIST@MITVMA.MIT.EDU
> Subject: Re: [PIC]:MPLAB floating point in C
>
>
> On 22-Feb-02 Rich Mcelroy wrote:
> > I'm using Bytecraft's compiler for MPLAB.  it does basic math, but the
> > results I'm getting indicate that it is droping anything after the integer
> > on my calculations.  I'm trying to calculate a percentage:
> >
> > Percent = A/B * 100;  something like that.  I have been getting a zero for
> > percent everytime.
>
> What are the types of A & B please ?
>
> If they are integers, then the result of the division will be an integer.
>
> I would try
>
> (100.0 * A) / B
>
> That should "promote" the result to be a floating point type.  See Page 44
> of
> the Second edition of K&R.
>
> Peter.

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