Re: change handling of time data for 5.0?

[Ethan A M. <sf...@us...>]

On Friday, 03 October, 2014 15:04:07 Karl Ratzsch wrote:

> > We already broke some backwards compatibility by adding a 2nd
> > parameter to
> > timecolumn(). The new version obviates the need for "set xdata time" to
> > handle input, although arguably it is uglier to put the information
> > in the
> > "using" part of every plot command rather than setting it only once via
> > "set xdata time; set timefmt x 'foo'".
> 
> Would it be difficult to make the second parameter to timecolumn()
> optional, and use whatever is set via "set timefmt" if no format
> string is given?

Yes, it is possible to trap the case of a single parameter and
fall back to a default timefmt.  That loses the ability to have
separate default formats for the x and y axes, but see below.

The whole idea of having the time format be per-axis rather than
per-datafile makes little sense to me.  So I'm now thinking we could
remove the timefmt field from (struct axis) and have one global default.
This is in fact what the 4.6 documentation describes, even though
it hasn't been true for a very long time.  So although it would
internally be a change, it would keep the previous documentated
behavior.  It would only affect scripts that used the undocumented
command: set timefmt y "format".

	Ethan