GIS and Remote Sensing Tools, Tips and more ..

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..

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])

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.

Open Source software has come a long way in recent years for storing, manipulating and presenting spatial data. The Openstreetmap (www.openstreetmap.org) project is a great example of what can be achieved using open software and open data. This presentation will look at using a combination of postgis, geoserver and openlayers to process, store and present vector and raster map data. The presentation will also demonstrate OGC web mapping protocols, map projections, spatial toolkits (including uDig, gdal and ogr) and sources of free geospatial data. Gavin Jackson is a software engineer working in the Spatial Team on the Atlas of Living Australia project (www.ala.org.au). Bio: A software engineer with 10 years experience (BInfTech ANU, Msc UNSW), he has worked in a variety of environments, including Department of Defence (IT Security), CPT Global (Stress and Volume Testing), Les Mills (Software Engineer) and, currently, CSIRO (Spatial Software Engineer).  He has long been an advocat...

Are you wondering on MODIS products' naming convention? Don't worry !!. This is the time to dig out MODIS names. Let's say you have few MODIS products. Nadir BRDF-Adjusted Reflectance  ( NBAR ): MCD43B4.A2000185.h25v03.005.2006299173851.hdf MODIS Land Surface Temperature Products: MOD11A2.A2002241.h12v02.005.2007222102136.hdf MCD43B4 or MOD11A2- MODIS Product Short Name A2000185 or A2002241 - Julian Date of Acquisition (A-YYYYDDD) h25v03 or h12v02- Tile Identifier (Tile location- horizontalXXverticalYY) 005 - Collection Version 2006299173851 or 2007222102136- Julian Date of Production (YYYYDDDHHMMSS) The YYYYDDD of above products equivalent to 2006299 and 2007222, which means Year:2006 Day of Year:299 (OCT 25, 2006) & Year:2007 Day of Year:222(AUG 09,2007) hdf - Data Format (HDF-EOS) Cheers !!

Creating a kmz image overlay  1. Make sure the dataset you are working with has a geographic coordinate system (unprojected) with WGS84 as the datum. If not, you will need to reproject your data. If the coordinate system of your datasets is defined you can change the projection “on-the-fly”. To reproject on-the-fly, go to Layers then Click Properties and specify geographic with WGS84 datum as the coordinate system. However, I recommend reprojecting the actual GIS datasets (shapefiles, grids, etc.) because project-on-the-fly is not always very precise, particularly when dealing with datum transformations. 2. Switch to the layout view. Select a layout that matches the dimensions of your map as closely as possible. To keep the file sizes of your images small, try to leave as little empty space around the edges as possible. Right-click on the layout and select Page and Print Setup to change the layout size. 3. Right-click on the map and select Properties. Go to the Size and Posit...

Time lapse sequences of photographs taken with a special low-light 4K-camera (made in Japan)  by the crew of expedition 28 & 29 onboard the International Space Station from  August to October, 2011. Shooting locations in order of appearance: 1. Aurora Borealis Pass over the United States at Night 2. Aurora Borealis and eastern United States at Night 3. Aurora Australis from Madagascar to southwest of Australia 4. Aurora Australis south of Australia 5. Northwest coast of United States to Central South America at Night 6. Aurora Australis from the Southern to the Northern Pacific Ocean 7. Halfway around the World 8. Night Pass over Central Africa and the Middle East 9. Evening Pass over the Sahara Desert and the Middle East 10. Pass over Canada and Central United States at Night 11. Pass over Southern California to Hudson Bay 12. Islands in the Philippine Sea at Night 13. Pass over Eastern Asia to Philippine Sea and Guam 14. Views of the Mideast at Night 15....