Re^3: Strange int() result

How so? The OP's problem comes from the use of int function on a number calculated as 35784.45 * 100 and turning out to be very very slightly smaller than 3578445. It seems to me you probably read too quickly the OP. Example under the debugger:

  DB<10> $amount = 35784.45;

  DB<11> $amount =~ s/\.//;

  DB<12> print $amount;
3578445
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Re^4: Strange int() result by hexcoder (Curate) on Jun 18, 2014 at 21:38 UTC
Very interesting test! I could not understand at first why multiplying with an even integer factor would introduce rounding errors. So it seemed, but when I went one step back and ignored the multiplication I saw: the value itself is not expressible as a fixedpoint binary number. So there are two ways to look at it (numerically and as a string): `$ perl -wE '$x=35784.45; printf "%.15f\n%s", $x, $x;' 35784.449999999997090 35784.45` [download] Since now I always assumed the string representation were made from the numerical representation thus giving the same output. That was obviously wrong. Update: A second counter test `$ perl -wE '$x=35784.449999999997090; printf "%.15f\n%s", $x, $x;' 35784.449999999997090 35784.45` [download] reveals: the string representation always uses some rounding.	[reply] [d/l] [select]
Re^5: Strange int() result by Laurent_R (Canon) on Jun 18, 2014 at 22:15 UTC
Another test under the debugger to give you food for thought: `DB<13> printf "%d", 35784.45 * 100; 3578444 DB<14> printf "%s", 35784.45 * 100 3578445` [download] But the real question was addressed earlier by davido: where is the 35784.45 piece of data coming from? If it is read in a text file or from a text-format network, then using regexes or `printf "%s", ...` is not only right, but is probably the best solution. If it comes from a previous calculation or from binary data, then it may be slightly more complicated, details would be needed about its original format.	[reply] [d/l] [select]
Re^4: Strange int() result by flowdy (Scribe) on Jun 18, 2014 at 20:37 UTC
Thanks, got the point. Shame on me.	[reply]