Hi Friedrich: For land-use a class would be for example forest, other would be orchard etc. For Slope gradient I would have values which <3 and between 3 and 7 etc. So, I will have 2 raster data with, let's say, 3 classes each: forest, orchards and built-up area and for slope gradient: 0-3, 3-15, 15-35. The cross-tabulation analysis should give me a table like:
forest orchards built-up 0-3 10 20 15 3-15 5 10 20 15-35 5 15 15 where the numbers represents all the common cells, for example: 10 cells with forest correspond to 10 cells with 0-3 slope gradient interval and so on (by cells I mean the pixel from a raster data) The analysis is better illustrated here: http://webhelp.esri.com/arcgisdesktop/9.2/index.cfm?TopicName=tabulate_area Ionut ________________________________ From: Friedrich Romstedt <friedrichromst...@gmail.com> To: Discussion of Numerical Python <numpy-discussion@scipy.org> Sent: Sun, July 18, 2010 12:09:04 AM Subject: Re: [Numpy-discussion] Crosstabulation 2010/7/17 Robert Kern <robert.k...@gmail.com>: > On Sat, Jul 17, 2010 at 13:11, Friedrich Romstedt > <friedrichromst...@gmail.com> wrote: >> 2010/7/14 Ionut Sandric <sandricio...@yahoo.com>: >> I'm afraid also Zach does not understand what you are talking about >> ... So my first question (please bear with me) would be: What's a dem? > > Digital Elevation Map. > >> (n/a in my dictionary) And sorry for the cross-talk on the other >> first post by you ... >> >> And by slope gradient you mean second derivative? > > No, the first derivative. "Slope gradient" is a reasonably common, > albeit somewhat redundant, idiom meaning the gradient of an elevation > map. Thanks Robert, that clarifies a lot. But still I don't understand how the crosstabulation shall work. What are the "classes"? Friedrich _______________________________________________ NumPy-Discussion mailing list NumPy-Discussion@scipy.org http://mail.scipy.org/mailman/listinfo/numpy-discussion
_______________________________________________ NumPy-Discussion mailing list NumPy-Discussion@scipy.org http://mail.scipy.org/mailman/listinfo/numpy-discussion