I Cannot Seem To Find The Correct Formatting Spec For Preceding Zeroes In Python

When adding decimal places, it's as simple as john = 2 johnmod = format(john, '.2f') print(johnmod) and I get 2.00 back, as expected. But, what's the format spec for adding p

Solution 1:

Several Pythonic ways to do this,:

First using the string formatting minilanguage, using your attempted method, first zero means the fill, the 4 means to which width:

>>> format(2, "04")
'0002'

Also, the format minilanguage:

>>> '{0:04}'.format(2)
'0002'

the specification comes after the :, and the 0 means fill with zeros and the 4 means a width of four.

New in Python 3.6 are formatted string literals:

>>>two = 2>>>f'{two:04}'
'0002'

Finally, the str.zfill method is custom made for this:

>>> str(2).zfill(4)
'0002'

Solution 2:

Use zfill:

john = 2
johnmod = str(john).zfill(4)
print(johnmod) # Prints: 0002

Solution 3:

You were nearly there:

johnmod = format(john, "04d")

Solution 4:

format(john, '05.2f')

You can add the leading 0 to a floating point f format as well, but you must add the trailing digits (2) and the decimal point to the total.