function exp returns same value regardless of input in ABDKMath64x64 about abdk-libraries-solidity HOT 4 CLOSED

Both, argument and result are 64.64-bit fixed point numbers, so 1 means 1*2^-64, and 18446744073709551616 means 18446744073709551616*2^-64. This number format is used for almost all functions within ABDKMath64x64 library. Where different number format is used, it is stated in docstring.

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Hey @bgits, you may find useful this number converter developed by @3sGgpQ8H:

https://toolkit.abdk.consulting/math#convert-number

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What arguments did you try? Due to rounding errors, exp(x) may return the same value for different arguments in case argument values are close enough.
In my experiments exp(1)=18446744073709551616 but exp(2)=18446744073709551617, so different results for different arguments.

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Perhaps I'm misunderstanding the function, my understanding is that is should return e^x, in which case exp(1) = 2..., exp(2) = 7....

If the intention is as above then the calculation is off, otherwise perhaps a clarification on the function docstring.

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