I am using grass-6.4.2 for generation of heat maps of crime data. For testing purpose, I created a vector layer from my places shapefile which is a point data.The places shapefile contains more than 3000 data.I used v.kernel command for generation of raster map as follows:
g.region rows=20 cols=20 v.kernel input=Places@PERMANENT output=raster1 stddeviation=0.001
But the output was a rectangle. I increased the
stddeviation value step by step to 10000. The output has
Maximum value in output: 1.591528e-11. but the raster image is completely wrong. Please help me in solving this issue.
I checked with rows=600 and columns=600 with a standard deviation of 1000. Here is the output I got:
(Thu Nov 15 11:05:14 2012) Command finished (0 sec) (Thu Nov 15 11:06:05 2012) v.kernel input=Places@PERMANENT output=raster3 stddeviation=10000 STDDEV: 10000.000000 RES: 1324.680000 ROWS: 600 COLS: 600 Writing output raster map using smooth parameter=10000.000000. Normalising factor=648263501.877776. Maximum value in output: 1.589441e-09. (Thu Nov 15 11:06:07 2012) Command finished (2 sec)
All I get is several rings with different colors radiating from the center.
Thanks in advance.