Hi monks,

i know perl is not aim at doing calculation at first, but here is a simple thing i coded, and the result is quite strange, could someone explain me why , and if there is a solution to avoid this, it would be welcomed !

I just add recursively 0.1 to a number, and sometime i got more than 1 decimal !

here is the code, following by the output : 
#!/usr/bin/perl -w

use strict;
use warnings;

my $bou = 20;
my $beu = 0.1;

my $nb=$bou/$beu;
my(@bu);
$bu[0]=0;
for (my $i=1;$i<=2*$nb;$i++){

    $bu[$i]=$bu[$i-1]+$beu;    
    print "$i\t$bu[$i]\n";
}

[download]
and it gives : 
1       0.1
2       0.2
3       0.3
4       0.4
5       0.5
6       0.6
7       0.7
8       0.8
9       0.9
10      1
11      1.1
...
55      5.5
56      5.6
57      5.7
58      5.8
59      5.9
60      5.99999999999999
61      6.09999999999999
62      6.19999999999999
63      6.29999999999999
64      6.39999999999999
65      6.49999999999999
66      6.59999999999999
67      6.69999999999999
68      6.79999999999999
69      6.89999999999999
70      6.99999999999999
71      7.09999999999999
72      7.19999999999999
73      7.29999999999999
...
98      9.79999999999998
99      9.89999999999998
100     9.99999999999998
101     10.1
102     10.2
103     10.3
104     10.4
105     10.5
...
223     22.3
224     22.4
225     22.5
226     22.6000000000001
227     22.7000000000001
228     22.8000000000001
229     22.9000000000001
230     23.0000000000001
231     23.1000000000001
232     23.2000000000001
233     23.3000000000001
...
396     39.6000000000003
397     39.7000000000003
398     39.8000000000003
399     39.9000000000003
400     40.0000000000003

[download]
Thanks, Marcel

In reply to strange result for a simple addition ?? by Marsel

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