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Posted by Carlos on March 17, 2001 at 10:38 PM
Your reply was very helpfull I was afraid something like this was happening, do you know an easy way to round off floats?
> i'm replying to myself after obtaining
> more information about the subject.
> this is not a bug, but how IEEE floating
> point operates.
> excerpt from a helpful respond :
> With float and double values, if you want certain rounding behavior,
> then you must provide for that in your code. The Java language does
> not do any rounding by default. In fact, the Java Language Specification
> (JLS) prohibits rounding by default. This surprises many people who are
> familiar with the rounding done automatically by the C language run-time
> This is not a problem with the Java Language.
> All IEEE floating point arithmetic is inexact. This
> is the inescapable consequence of storing the results
> in a finite number of bits (32 for float and 64 for
> You are operating at the limits of IEEE floating point accuracy.
> As described in the standard: ANSI/IEEE STD 754-1985 (IEEE
> Standard for Binary Floating-Point Arithmetic), when using
> double values (which have roughly 18 decimal digits of
> precision), every calculation introduces an error of about
> 1.0E-17. For float values (having about 8 decimal digits of
> precision), every calculation introduces an error of at least
> hope this help others that doesn't realize this already.