Re: Why do these values not match?

I wouldn't say it's a bug. It happens in all programming languages, not just PHP. I'd rather call it "loss of precision". A decimal number isn't just what you see. 332.06 doesn't mean it only contains 2 digits. I don't know much about it, but cast a float number into a string certainly will get your job done. Or find a function that does that for you (I don't know which one). Tony S. Wu szii@sziisoft.com at szii@sziisoft.com wrote: > Looks like a bug in PHP since the types are both > set correctly and appear equal. Doing a cast/recast > should never change the "value" and have it suddenly > compare okay via the last "!=" operator. > > Filed report Bug #17984 along with attached script. > > <?php > > $a = 332.06; > $b = 45.11 + 134.38 + 85.35 + 67.22; > > echo "output\n"; > > var_dump($a); > var_dump($b); > > print("Total = $a\n"); > print("Production = $b\n"); > > > if($a != $b) > { > print("Totals do not Match!\n"); > } > else { > print("Totals are in Balance\n"); > } > > if($a !== $b) > { > print("Totals do not Match!\n"); > } > else { > print("Totals are in Balance\n"); > } > > if($a <> $b) > { > print("Totals do not Match!\n"); > } > else { > print("Totals are in Balance\n"); > } > > if($a > $b) > { > print("a is greater!\n"); > } > else { > print("b is greater!\n"); > } > > settype($a,"string"); > settype($b,"string"); > > if ($a != $b) > echo "String compare failed!\n\n"; > > > settype($a,"float"); > settype($b,"float"); > > if ($a != $b) > echo "recast to float compare failed!\n\n"; > > echo "end output\n"; > ?> > > ----------------------------- > output > float(332.06) > float(332.06) > Total = 332.06 > Production = 332.06 > Totals do not Match! > Totals do not Match! > Totals do not Match! > b is greater! > end output > ------------------------------ > > Summary: > float compare fails (!=) > float compare fails (<>) > float compare fails (!==) > "b" is somehow greater than "a" > cast to string, compare okay. > recast to float, compare okay. > > -Mike