fmt_num.RdFormat numeric value
fmt_num(x, digits, width = digits + 4)an atomic numerical or character object, possibly
complex only for prettyNum(), typically a
vector of real numbers. Any class is discarded, with a warning.
the desired number of digits after the decimal
point (format = "f") or significant digits
(format = "g", = "e" or = "fg").
Default: 2 for integer, 4 for real numbers. If less than 0,
the C default of 6 digits is used. If specified as more than 50, 50
will be used with a warning unless format = "f" where it is
limited to typically 324. (Not more than 15--21 digits need be
accurate, depending on the OS and compiler used. This limit is
just a precaution against segfaults in the underlying C runtime.)
the total field width; if both digits and
width are unspecified, width defaults to 1,
otherwise to digits + 1. width = 0 will use
width = digits, width < 0 means left
justify the number in this field (equivalent to flag = "-").
If necessary, the result will have more characters than
width. For character data this is interpreted in characters
(not bytes nor display width).