On Tue, Jan 06, 2015 at 03:35:23PM +0000, Moriceau, Julien wrote: > It is my first message to you guys because I am struggling with > gwyddion (I precise I am a new user). > I have AFM files that I want to analyze, but a lot of these files are > containing NaN value. > I can open these images without too much trouble but the software > cannot calculate any of the advanced statistical data (as HHCF that I > am interested in) because, I guess, of the NaN values. > Is there any way to correct this problem? Or not to take in account > NaN during calculation? (the calculation is working well with the > height distribution for example).
Hello, Gwyddion does not work with NaNs. Some function may do something meaningful when encounterng data containing NaNs, but only by coincidence, not by design. The normal handling is to replace undefined values with some ‘neutral’ value upon import and create a mask covering the invalid pixels. It is possible that this treatment is missing in the import of some file format where we did not expect NaNs to occur. Please post in which file format you encounter the NaNs so that we can fix its import. When you have the data with mask over invalid pixels you can - exclude the masked area from processing in functions that support this - apply some interpolation or arithmetic function to replace the masked pixels with other suitable values - use the entire image in functions that require a regular area (most of the advanced ones) Regards, Yeti ------------------------------------------------------------------------------ Dive into the World of Parallel Programming! The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net _______________________________________________ Gwyddion-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/gwyddion-users
