Format numbers to strings in Python

David Ackerman picture David Ackerman · Aug 22, 2008 · Viewed 345.5k times · Source

I need to find out how to format numbers as strings. My code is here:

return str(hours)+":"+str(minutes)+":"+str(seconds)+" "+ampm

Hours and minutes are integers, and seconds is a float. the str() function will convert all of these numbers to the tenths (0.1) place. So instead of my string outputting "5:30:59.07 pm", it would display something like "5.0:30.0:59.1 pm".

Bottom line, what library / function do I need to do this for me?

Answer

Konrad Rudolph picture Konrad Rudolph · Aug 22, 2008

Starting with Python 3.6, formatting in Python can be done using formatted string literals or f-strings:

hours, minutes, seconds = 6, 56, 33
f'{hours:02}:{minutes:02}:{seconds:02} {"pm" if hours > 12 else "am"}'

or the str.format function starting with 2.7:

"{:02}:{:02}:{:02} {}".format(hours, minutes, seconds, "pm" if hours > 12 else "am")

or the string formatting % operator for even older versions of Python, but see the note in the docs:

"%02d:%02d:%02d" % (hours, minutes, seconds)

And for your specific case of formatting time, there’s time.strftime:

import time

t = (0, 0, 0, hours, minutes, seconds, 0, 0, 0)
time.strftime('%I:%M:%S %p', t)