Math::Fraction uses faulty logic
| From: | Colin Viebrock | Date: | Tue, 13 Nov 2001 23:27:53 +0000 |
| Subject: | Math::Fraction uses faulty logic | ||
| Groups: | php.pear.dev | ||
| Request: | Send a blank email to pear-dev+get-2876@lists.php.net to get a copy of this message | ||
I'm pretty sure the logic in Math::Fraction for adding and subtracting
fractions is wrong.
Given: n1 n2
---- + ----
d1 d2
The current code basically says the answer is:
( n1 + n2 )
-------------
( d1 * d2 )
Try that for 1/2 + 1/4 and you'll see it should be:
( n1 * d2 ) + ( n2 * d1 )
---------------------------
( d1 * d2 )
Similarly, subtracting should be:
( n1 * d2 ) - ( n2 * d1 )
---------------------------
( d1 * d2 )
- Colin