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Old 2019-08-07, 21:33   #1
baih
 
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Jun 2019

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Default Question about Exponentiation modulaire

how to calculate pow(2,23571176971393,1523213.17)

I mean
pow(a,e,b)
with b non integer = 123213.17

Have a nice day. :)
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Old 2019-08-09, 14:21   #2
lavalamp
 
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Default

For the specific case of 1523213.17, you could compute mod 152321317 instead, then once you have that value use it to compute your final float mod.

In general, I suppose it depends on how many decimal digits you have and how much precision you need, but multiplying your modulo by 10^n should work decently well for many inputs.
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