circuitpython/tests/float/string_format_modulo2.py

25 lines
834 B
Python

# test formatting floats with large precision, that it doesn't overflow the buffer
def test(num, num_str):
if num == float('inf') or num == 0.0 and num_str != '0.0':
# skip numbers that overflow or underflow the FP precision
return
for kind in ('e', 'f', 'g'):
# check precision either side of the size of the buffer (32 bytes)
for prec in range(23, 36, 2):
fmt = '%.' + '%d' % prec + kind
s = fmt % num
check = abs(float(s) - num)
if num > 1:
check /= num
if check > 1e-6:
print('FAIL', num_str, fmt, s, len(s), check)
# check pure zero
test(0.0, '0.0')
# check some powers of 10, making sure to include exponents with 3 digits
for e in range(-8, 8):
num = pow(10, e)
test(num, '1e%d' % e)