[GRASS-user] Interpolate grid(s) based on vector.
Hello Grass List, I have a set of rasters (ground acceleration, modal mag., and distance) that I want to interpolate based on the location of my point features (borehole location) and update my point feature with the values from this interpolation. I see that v.what.rast might help, but I'm not sure what kind of interpolation it uses (probably nearest neighbor?). I also see that v.sample can be used, but it does not work with geographic coordinate system locations. So, I was hoping that the list might have other ideas in solving my problem. Thanks in advance! Bob Robert Moskovitz California Geological Survey Seismic Hazards Zonation Program CONFIDENTIALITY NOTICE: This communication is intended only for the use of the individual or entity to which it is addressed. This message contains information from the State of California, California Geological Survey, which may be privileged, confidential and exempt from disclosure under applicable law, including the Electronic Communications Privacy Act. If the reader of this communication is not the intended recipient, you are hereby notified that any dissemination, distribution, or copying of this communication is strictly prohibited. ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] Interpolate grid(s) based on vector.
Hi Bob, I have a set of rasters (ground acceleration, modal mag., and distance) that I want to interpolate based on the location of my point features (borehole location) and update my point feature with the values from this interpolation. I see that v.what.rast might help, but I'm not sure what kind of interpolation it uses (probably nearest neighbor?). I also see that v.sample can be used, but it does not work with geographic coordinate system locations. So, I was hoping that the list might have other ideas in solving my problem. I think it is best to approach the problem in two steps. First do your interpolations using a method appropriate to your data type, sampling density, sensitivity to outliers, etc. Then once you have your interpolated surface run v.what.rast, or v.rast.stats, or from addons v.rast.stats2 or v.what.rast.buffer depending if you want to pick off the exact interpolated value at a given site, a statistical indicator for values around that site (e.g. variance) as either a buffer distance or within a given vector polygon. By the way, we are currently discussing / upgrading the v.krige offerings, you're most welcome to weigh in on the conversation if that's what you're after. Hamish ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
