[gtkextra] bug in gtkplotps.c found

[Tobias R. <ya...@gm...>]

hi!

i'm writing a little program using your wonderful gtk+extra widgetset
(version 0.99.16).

when plotting the chart into a postscript file i sometimes got errors while
opening the file with external programs like 'gv'. but thank to gnu's
license i was able to fix the bug within one day. the patch is appended to
the mail.

the functions psdrawlines() and psdrawpolygon() print at least one data point
 - even if there are no points at all (argument numpoints = 0). thus they use
pointers to false data. these situation sometimes occured in my program. once
i got a floating-point number in the ps file with over 250 digits!

please check if similar buggy code is also used in other functions within
the gtk+extra widgets (as we often copy code and modify it for our needs).

greetings,
tobias

-- 
Tobias Rapp  --  Homepage: http://yahuxo.de