Re: timecolumn()

[Ethan M. <merritt@u.washington.edu>]

On Thursday 05 May 2005 07:52 am, Hans-Bernhard Broeker wrote:
> 
> The obviously correct solution would be to pass a timeformat string 
> directly as a second argument to timecolumn().  Back when I added 
> per-axis timefmt strings, that wasn't possible.  Nowadays, with the 
> stringvariables patch integrated, it probably is.

Yes. Passing a string as a 2nd argument (or even a string-valued
function) is easy.  The hard part would have been to retain
backward-compatibility with scripts using only one argument.
Fortunately timecolumn was a secret undocumented function,
so there are no such scripts :-)

But before anyone plunges in, I point out that there is probably
another approach that should be considered.  If the task is
specifically to read time info from the file and associate it
with axis labels, then I think this is almost possible already
by passing a sting-function to the [xyz]xticlabels option.
The following doesn't quite work, but could be made to work:

   timeformat = "some time format"
   plot 'foo' using 4:5:xtic(gprintf(timeformat,column(1)))

The trick would be to extend routine plot_ticlabel_using(int axis)
in datafile.c so that it parses the argument to xtic() as a
general expression rather as an integer constant.  That's something
I meant to do originally, but never got around to it.  It would
have uses beyond timeformats, of course.


-- 
Ethan A Merritt       merritt@u.washington.edu
Biomolecular Structure Center
Mailstop 357742
University of Washington, Seattle, WA 98195