>>> Nikos Alexandris <[email protected]> 03/03/09 9:04 AM >>> Wesley: > I got the svn grass6_devel code from the location you suggested and have > now installed but with lots of errors. Here is the output from the > 'make' command (see below the lapack.h error). I understand that I need > to cd into the directory where the error occurred and run make inside > that directory. I do this for the gmath directory and I once again > receive an error message related to the lapack.h file. The same error > occurs when running make in other error locations.
> /usr/local/src/grass6_devel/dist.i686-pc-linux-gnu/include/grass/lapack.h:5144: > error: expected declaration specifiers or ‘...’ before ‘ftnlen’ > make: *** [OBJ.i686-pc-linux-gnu/del2g.o] Error 1 Wesley, what are the exact steps you are executing in order to compile grass6_devel? (assuming you work under linux) If you already had done a compilation before, did you "make distclean" before re-compiling? (or "sudo make distclean"). I actually figured out the problem about 10 min after I sent you and the list the mail. My apologies (that actually happens fairly often), I found the following entry while searching the mail archives of this list. http://lists.osgeo.org/pipermail/grass-user/2007-January/038085.html My error was related to the lapack.h file which is not used in Grass so I removed '--with-blas --with-lapack' from my ./configure and hey presto, everything works fine in the development version, except nviz, which I am not too concerned about. > I dont have much more time to spend on this so would ideally just like > to get the i.pca working in development installation so that I can use > i.pca and get the variance and eigen values. In my tests run so far I > have seen that i.pca produces more realistic results, based on > qualitative assessment. As such, I will use i.pca instead of the > 'by-hand-method' If you don't mind to share some more info about the way you assess the quality of the components (just even mentioning some will be great - I am really interested in it). To be honest I just assess the resulting images visually and see if for eg. PC1 looks to contain information from both the lidar and aerial photography. While assessing the results from the 'by-hand' method I noticed that my lidar data did not really contribute to the first PC component. Given that both data sets were largely made up of canopy information I was hoping that PC would contain more canopy info from the lidar data. Assessing the result of a PCA is fairly difficult I think. In past research I ran a time series analysis on 20years of NDVI data and used PCA to analyse trends. Correlation between PC component 1 and the time series data set generally returned seasonal variations in the data set. In the present analysis I guess you could do the same although I am not really sure how useful that would be. For me I would just like to make sure that I am running the analysis correctly and that the resulting fusion of the aerial photographs and lidar canopy models contributes to an enhanced ability to count tree canopies. When I went back to tests run using the original i.pca I saw that the first PC seemed to contain more information from both data sets. I am now running a test using the new i.pca (grass_devel6) with all input data scaled to 8 bit grey scale and centered using the global mean of each band. Combined with the changes made by Hamish, I think this final test will prove very successful. > > Thanks for all your help wrt running pca in grass. > Wesley Thanks to the community and Hamish for his time. Nikos Yes, indeed, thanks to Hamish and the rest of the grass-user community Wesley -- This message is subject to the CSIR's copyright terms and conditions, e-mail legal notice, and implemented Open Document Format (ODF) standard. The full disclaimer details can be found at http://www.csir.co.za/disclaimer.html. This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean. MailScanner thanks Transtec Computers for their support. _______________________________________________ grass-user mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-user
