#keep
# Never mind the details of this function...
def pretty_print_fp(x):
print("---------------------------------------------")
print("Floating point structure for %r" % x)
print("---------------------------------------------")
import struct
s = struct.pack("d", x)
def get_bit(i):
byte_nr, bit_nr = divmod(i, 8)
return int(bool(
s[byte_nr] & (1 << bit_nr)
))
def get_bits(lsb, count):
return sum(get_bit(i+lsb)*2**i for i in range(count))
# https://en.wikipedia.org/wiki/Double_precision_floating-point_format
print(" 1 2 3 4 5")
print("indices : 012345678901234567890123456789012345678901234567890123456789")
print("Sign bit (1:negative):", get_bit(63))
exponent = get_bits(52, 11)
print("Exponent (binary):", bin(exponent)[2:])
print("Exponent (shifted): %d" % (exponent - 1023))
fraction = get_bits(0, 52)
significand = fraction + 2**52
print("Significand (binary):", bin(significand)[2:])
print("Significand (shifted):", repr(significand / (2**52)))
#keep
pretty_print_fp(2**1024)
Things to try:
float("nan")
import numpy as np
np.binary_repr(1024)
bin(1024+1023)