v.rast.stats - ERROR: No categories found in raster map

I was  experiencing "ERROR: No categories found in raster map" during v.rast.stats computation (Zonal statistics in terms of ESRI, ArcMap).

From the GRASS documentation, I learned that v.rast.stats is only designed for vector areas, not for lines, points,face,centroid,boundary, etc.

Therefore, I  unchecked all the properties of vector layer except area as in figure 2, and run the v.rast.stats- worked like charm..

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Interesting cheat sheets for R beginner

To clear the console: CTRL + L

To seek help: ?command_name

To view type:class(object_name)

To maximize the console print view: Options(max.print=999999)

To list active objects in R: ls()

To Remove single object:rm(object_name)

To Remove all Objects in R: rm(list=ls())

To remove all the objects - except 'a': rm(list = ls()[-a])

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An Interactive Visualization using Geoserver & Openlayers

From last couples of week, I have been involving to develop a interactive web interface for West Nile virus incidence dissemination across the conterminous US from 1999-2011.

The image on the right shows one of my accomplishment using
Geoserver,Openlayers,jQuery, PostgreGIS,and Google API. The project is about to launch online, then I will post a complete link of the project to let you guys play around it.

Click to visit: Web application

I am willing to help any one who is stuck with web maps/visualization and also seek constructive criticism on web stuffs.

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