Beefy Boxes and Bandwidth Generously Provided by pair Networks
laziness, impatience, and hubris
 
PerlMonks  

Re: Comparing results of math operations

by zentara (Archbishop)
on Apr 16, 2014 at 09:50 UTC ( #1082474=note: print w/ replies, xml ) Need Help??


in reply to Comparing results of math operations

Here is another textbook example which demonstrates the problem. You need to specify how many digits of accuracy you need for the comparison, and round your floats off accordingly.
#!/usr/bin/perl -w use strict; my ( $number, $premium, $expected ); $number = 1.80; $premium = $number * ( 1 + 10/100 ); # 1.8 + 10% of 1.8 $expected = 1.98; # As we know 1.8 + 10% of 1.8 is 1.98 printf "Number 1 : %20.19f\n", $premium ; printf "Number 2 : %20.19f\n", $expected ; print "Not" if ( $expected != $premium ); print "Equal !! "; __END__ Number 1 : 1.9800000000000002043 Number 2 : 1.9799999999999999822 NotEqual !!

I'm not really a human, but I play one on earth.
Old Perl Programmer Haiku ................... flash japh

Log In?
Username:
Password:

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://1082474]
help
Chatterbox?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others musing on the Monastery: (10)
As of 2016-08-25 19:10 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?
    The best thing I ever won in a lottery was:















    Results (362 votes). Check out past polls.