Comment on Why doesn't GCC optimize a*a*a*a*a*a to (a*a*a)*(a*a*a)? (2013)parentComments−TeMPOraL12yComparing floats for equality is equivalent to comparing them with tolerance that you don't control. I don't see a good reason to risk like that.−millstone12yComparing floats for equality is equivalent to a comparison with zero tolerance, not an uncontrolled tolerance.Consider storing a timestamp as a number of seconds since the epoch. We might use == to check if the timestamp has changed.−nitrogen12yRead the wikipedia entry on IEEE754-1985 (it has better diagrams than the main 754 entry): http://en.wikipedia.org/wiki/IEEE_754-1985#Representation_of...Knowing is better than fearing.−stephencanon12yNo, it's not equivalent to that at all. Why would you think such a thing?
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Comparing floats for equality is equivalent to comparing them with tolerance that you don't control. I don't see a good reason to risk like that.
Comparing floats for equality is equivalent to a comparison with zero tolerance, not an uncontrolled tolerance.
Consider storing a timestamp as a number of seconds since the epoch. We might use == to check if the timestamp has changed.
Read the wikipedia entry on IEEE754-1985 (it has better diagrams than the main 754 entry): http://en.wikipedia.org/wiki/IEEE_754-1985#Representation_of...
Knowing is better than fearing.
No, it's not equivalent to that at all. Why would you think such a thing?