Return a copy of the string left filled with ASCII '0' digits to make
a string of length width.
Usage
pystr_zfill(str, width)
Arguments
str
A character vector.
width
An integer.
Value
A character vector.
Details
A leading sign prefix (+/-) is handled by inserting the padding after
the sign character rather than before. The original string is returned if
width is less than or equal to nchar(str).