Hi Aaron, Well, the bad news is that this is on the trickier end of the GIS spectrum.
It depends on the exact nature of the conversion you want to perform when changing to polygon. http://gis.stackexchange.com/questions/23203/how-to-calculate-raster-statistics-for-polygons http://www.qgistutorials.com/en/docs/sampling_raster_data.html Should hopefully get you started though. Cheers, Jonathan From: [email protected] [mailto:[email protected]] On Behalf Of Aaron Stoler Sent: Monday, February 23, 2015 8:42 PM To: [email protected] Subject: [Qgis-user] pixel counts Hi all, I am brand new to QGIS and have pretty minimal GIS experience, so I apologize for my crude terminology. I was recently handed a large number of ARCInfo files (adf) containing information on species abundance at 30 m2 resolution. Each file (well...group of files since they are adf files) describes the abundance of a single species. I would like to analyze single species density within a custom-defined polygon. Species abundance within a 30 m2 is defined by color intensity (black = 0 abundance, white = max abundance). I have figured out how to view single adf files as raster layers in QGIS. From there, it seems like I should be able to generate a polygon and tell the program to analyze pixel count for each level of color intensity. I haven't had much GIS training, but I would really like to conduct an experiment that needs this data. Could someone please point me in the right direction? Thank you for your time, Aaron [email protected]<mailto:[email protected]> This message has been scanned for viruses by MailControl<http://www.mailcontrol.com/>, a service from BlackSpider Technology Click here<https://www.mailcontrol.com/sr/Q!YzIRnqaYfGX2PQPOmvUihCLhWP7Wj9u0zsJqkLFKbdzpao5qnPAtcTKz+bn8iTO+7meZyhI24DMGoTToeXlw==> to report this email as spam. ________________________________ HR Wallingford and its subsidiaries uses faxes and emails for confidential and legally privileged business communications. They do not of themselves create legal commitments. Disclosure to parties other than addressees requires our specific consent. We are not liable for unauthorised disclosures nor reliance upon them. If you have received this message in error please advise us immediately and destroy all copies of it. HR Wallingford Limited Howbery Park, Wallingford, Oxfordshire, OX10 8BA, United Kingdom Registered in England No. 02562099 ________________________________
_______________________________________________ Qgis-user mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/qgis-user
