You've just run into a problem that computer programmers have dealt with for decades: floating point numbers do not form a closed set under the operations of normal arithmetic. The reason is, of course, that floating point numbers only represent a finite subset of rational numbers.

Information about American English usage here and here. Floating point issues? Please read this before posting. — emc

In reply to Re: perl subtraction by swampyankee
in thread perl subtraction by jagdish.eashwar

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