Re: [math-fun] Name for function IEEE32(x) LOGAND -2^23 ??

3 Apr 2017

      Hmmm...

In Lisp this can be (expensively) computed by

(/ x (decode-float x))

i.e.,

(/ pi (decode-float pi)) == 4.0

decode-float returns as its first value a float
whose exponent is set to zero, so we can divide
by this number to wipe out the mantissa.

At 01:52 PM 4/3/2017, Henry Baker wrote:
...
Is there a name for the function that simply
kills all of the bits of precision from an
IEEE floating point number, leaving it as a
simple power of 2 ?
For a big-endian machine, pick up the 32 bits
of the IEEE32 float and AND it with -2^23.
Or pick up 64 bits of IEEE64 float and AND it
with -2^52.