fpconst.py 文件源码

def _zero_mantissa(dval):
    """Determine whether the mantissa bits of the given double are all
    zero."""
    bb = _double_as_bytes(dval)
    return ((bb[1] & 0x0f) | reduce(operator.or_, bb[2:])) == 0

##
## Functions to test for IEEE 754 special values
##