python の有効数字

number_print.py

print('{:.3f}'.format(123.456))
# 123.456
print(f"{0.12345678:.3f}")
# 0.123

# Other Examples

print('{:.3e}'.format(123.456))
print('{:.3g}'.format(123.456))
print('{:.3}'.format(123.456))
# 1.235e+02
# 123
# 1.23e+02

print('{:.8f}'.format(123.456))
print('{:.8e}'.format(123.456))
print('{:.8g}'.format(123.456))
print('{:.8}'.format(123.456))
# 123.45600000
# 1.23456000e+02
# 123.456
# 123.456