Re: [Gretl-devel] Call gnuplot within a function
On Sat, 12 Dec 2015, Sven Schreiber wrote:
Am 12.12.2015 um 10:43 schrieb Artur Tarassow:
> Just one remark on this:
> I had to replace:
> <hansl>
> S1 += "L1.$i "
> </hansl>
> by
> <hansl>
> S1 += "L1.$i,"
> </hansl>
> in case the list contains more than one variable.
What? That is weird, I would have thought that it produces a
syntax error later.
Artur's quite right, and it may be worth explaining why. The thing
is that "gnuplot" is gretl's ur-plotting command, and right now
"plot" is basically syntactic sugar for a complex "gnuplot"
instance.
In "gnuplot", the "with-impulses" option is a regular command
option, and since we don't want the elements of such a syntactic
unit to come unstuck from each other, we insist that they're joined
with commas, as in
gnuplot <whatever> --with-impulses=foo,bar
And the "plot" command as it currently exists inherits this
limitation.
It would be good to reverse the order of dependency -- in other
words, to make the signature of the underlying libgretl plotting
function consistent with a sensible syntax for "plot", and to turn
"gnuplot" into a driver for "plot" rather than vice versa. But this
will be quite a lot of work and it's not the most pressing item on
our agenda.
Allin