[TAG] Talkback:143/sephton.html

[Mauro Orlandini - IASF/Bologna]

Talking about rounding, I almost went crazy to find out why a perl program 
I was writing did not give the right result. Here is the code:

----------------------------------------------
#!/usr/bin/perl
#
$f = 4.95;
$F = (4.8+5.1)/2;
$F_spr = sprintf("%.10f", (4.8+5.1)/2);

printf "     f: %32.30f\n", $f;
printf "     F: %32.30f\n", $F;
printf " F_spr: %32.30f\n", $F_spr;

if ($f == $F) { print "\n f equals F!\n\n"; }
--------------------------------------------------

The test fails even if $f and $F are the same! I solved by using $F_spr 
instead of $F, but it took me a day to find it out... 8-(

Ciao, Mauro
-- 
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