extract
Extract a double from this integer, but scale it down by the specified power of two in the process. If the integer is beyond the scale of a double but the scale would bring it in range, don't overflow.
Return
The integer times 2^-exponentBias, as a double.
Parameters
self
The integer to convert to a double.
exponent
The scale by which the result's exponent should be adjusted (a positive number scales the result downward).