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# Tests various constants of the math module.
import sys
try:
from array import array
from math import e, pi
except ImportError:
print("SKIP")
raise SystemExit
# Hexadecimal representations of e and pi constants.
e_truth_single = 0x402DF854
pi_truth_single = 0x40490FDB
e_truth_double = 0x4005BF0A8B145769
pi_truth_double = 0x400921FB54442D18
# Detect the floating-point precision of the system, to determine the exact values of
# the constants (parsing the float from a decimal string can lead to inaccuracies).
if float("1e300") == float("inf"):
# Single precision floats.
e_truth = array("f", e_truth_single.to_bytes(4, sys.byteorder))[0]
pi_truth = array("f", pi_truth_single.to_bytes(4, sys.byteorder))[0]
else:
# Double precision floats.
e_truth = array("d", e_truth_double.to_bytes(8, sys.byteorder))[0]
pi_truth = array("d", pi_truth_double.to_bytes(8, sys.byteorder))[0]
print("e:", e == e_truth or (e, e_truth, e - e_truth))
print("pi:", pi == pi_truth or (pi, pi_truth, pi - pi_truth))
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