gEDA-user: ngspice plotting issues

[John Doty]

On Aug 5, 2007, at 5:33 AM, Chitlesh GOORAH wrote:

> On 8/5/07, Amit wrote:
>> I was able to create a netlist using gschem -> gnetlist and ngspice
>> successfully loads it. I get to the point where I perform a tran
>> simulation but I am not able to plot it. When I try to run the  
>> command
>> 'plot out' I get an error 'Can't open viewport graphics'.
>
> I had this issue before, however I don't recall how I solved it.
> Perhaps I've installed libXt-devel or other X11 headers before  
> compiling.

That could be it. The message generally means ngspice can't, for one  
reason or another, communicate with X11. The problem could be as  
simple as not having the DISPLAY environment variable set: X11  
desktops will set it for you, but if you launch ngspice from outside  
the X11 world, you'll get that message. Happens to me occasionally on  
MacOSX, when I'll forget and launch it from a Terminal rather than an  
xterm. I suppose if I set DISPLAY manually it would work in that case  
(assuming X11 is running, of course).

John Doty              Noqsi Aerospace, Ltd.
http://www.noqsi.com/
jpd at noqsi.com