python - Displaying the output of a variable to more than 2 decimal places

Question

I'm trying to display the output of my addition to more than 2 decimal places.

import time
import random

max_number = 1000000.0
random_time = random.randrange(1, max_number-1) / max_number
range_key = int(time.time()) + random_time

range_key
>>> 1347053222.790799

print range_key
>>> 1347053222.79

How can I print the full number? If this were a function, how could I return the full number?

Answer 1

When turning a float into a string (printing does this automatically), python limits it to only the 12 most significant digits, plus the decimal point.

When returning the number from a function, you always get the full precision.

To print more digits (if available), use string formatting:

print '%f' % range_key  # prints 1347053958.526874

That defaults to 6 digits, but you can specify more precision:

print '%.10f' % range_key  # prints 1347053958.5268740654

Alternatively, python offers a newer string formatting method too:

print '{0:.10f}'.format(range_key)  # prints 1347053958.5268740654