%D = integer degrees %<width.precision>d = floating point degrees %M = integer minutes %<width.precision>m = floating point minutes %S = integer seconds %<width.precision>s = floating point seconds %E = label with E/W instead of +/- %N = label with N/S instead of +/-
If the xtics are left in the default state (set xtics numeric) the coordinate will be reported as a decimal number of degrees, and format will be assumed to contain normal numeric format specifiers rather than the special set above.
To output degrees/minutes/seconds in a context other than axis tics, such as
placing labels on a map, you can use the relative time format specifiers
%tH %tM %tS for strptime. See time_specifiers (p. ), strptime (p.
).