That's an improvement. It would be even better if it actually worked! I
hope these fixes make it what you had in mind.

/* signed */ int raw;

void convert()
{

     inches = f1 = f10 = -1;

     while (raw >= 0) { raw -= 1200; f10++; }

     raw += 1200;

     while (raw >= 0)  { raw -= 120; f1++;   }

      raw += 120;

     while (raw >= 0) { raw -= 10; inches++;}

     tenths = raw + 10;
}

This, with driving code, compiles to exactly the same size as my version
but would be significantly faster.  The big win is in checking for a
negative number as opposed to comparison to a constant.  On the other
hand the algorithm is a bit obscured, prolly not too bad in such a short
run of code.

...rob

Walter Banks wrote:

 >The comparisons of raw to a constant requires a subtract that can be
folded
 >into the raw-= constant
 >
 >  while (raw >= 1200) {
 >        raw -= 1200; f10++;
 >
 >The following code does this and should be significantly shorter and
almost
 >twice as fast
 >
 >Walter Banks
 >
 >void convert1()
 >{
 >
 >    inches = f1 = f10 = -1;
 >
 >    while (raw >= 0) { raw -= 1200; f10++; }
 >
 >    while (raw < 0)  { raw += 120; f1++;   }
 >
 >    while (raw >= 0) { raw -= 10; inches++;}
 >
 >    tenths = -raw;
 >}
 >

---
robert a moeser
http://www.piclist.com/member/ram--000a
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