[gradsusr] Overlay a bar chart to an existing plot in GRADS (grid plot)

[Lyndon Mark Olaguera]

Hi all,

I'm trying to plot a bar chart over a specific grid box in the attached
figure.
For example,

I want to plot a bar chart between lat 15N to 17.5N and lon 117.5E to 120E
using the grid value within this box from t 1 to last.
I converted these coordinates to grid coordinates using 'q w2xy'.
So that I can use the 'set parea xmin xmax ymin ymax' command.

The base plot is the attached figure (set gxout grid).

My problem is that, the base plot disappears when I'm plotting the bar
chart.

Is there a way to tell GrADS not to reinitialize the plot (overlay)?

I'll appreciate any help,

Many thanks,

Lyndon
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://gradsusr.org/pipermail/gradsusr/attachments/20170111/0912704b/attachment-0001.html 
-------------- next part --------------
A non-text attachment was scrubbed...
Name: test.png
Type: image/png
Size: 55173 bytes
Desc: not available
Url : http://gradsusr.org/pipermail/gradsusr/attachments/20170111/0912704b/attachment-0001.png