Floating-point equality and inequality -


floating-point equality comparison has weird edge cases e.g. 2 nan values compare not equal if identical bit patterns.

can assumed, however, inequality inverse of equality? is, assuming standard ieee 64-bit floating-point numbers implemented on mainstream architectures such x64, 1 of a == b , a != b true regardless of bit patterns present?

yes, true, there no number interpretations of bit patterns operator == not return exact opposite !=.

there exceptions bit patterns compare equal different bit patterns (negative 0 0x80... equal 0 0x00...) or same bit pattern compare unequal (nans) mentioned, != inversion of ==.


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