If you 'use bignum;' then both "10" and "$n" are Math::BigInt objects. I haven't checked it out, but I suspect that when you raise one Math::BigInt object to the power of another Math::BigInt object, the result is also a Math::BigInt object - which, in your case, needs to contain the value '0.1' .... but you can't expect a Math::BigInt object to hold such a value.

The following should produce the correct answer but doesn't: 
D:\>perl -Mbignum -e "print 10.0 ** -1.0"
NaN

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Unfortunately, the "10.0" and "-1.0" are simply being made into Math::BigInt objects with values of 10 and -1, respectively. If they were created as Math::BigFloat objects (as in my next one liner) everything would work fine: 
D:\>perl -Mbignum -e "print 10.1 ** -1.1"
0.07856814306418730376003456559872468142155

[download]

Cheers,
Rob

In reply to Re: use bignum and exponentiation by syphilis
in thread use bignum and exponentiation by swampyankee

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