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Comment on Why doesn't GCC optimize a*a*a*a*a*a to (a*a*a)*(a*a*a)? (2013)parent

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Pure cargo-culting. There are circumstances in which it’s perfectly appropriate to compare floating-point data for equality. There are also circumstances in which a comparison with some tolerance is more appropriate. Understand what situation you’re in, and understand the tools that you’re using.

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?

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