!!! We got it !!! That was exactly the root of all evil. The FFT was fine but the selection was spoofing the coordinates. I should have asked for that much earlier. Adding the x and y offset to every coordinate readout finally leads to reasonable values.
Many many thanks for your patience, yeti. We can finally close this chapter... Cheers, /M On 0, "David Nečas (Yeti)" <[email protected]> wrote: > On Tue, Sep 16, 2014 at 11:42:19AM +0200, Mathias Müller wrote: > > Honestly, I am kind of distressed. I do exactly the same. The image is > > of cause centered, but when extracting coordinates of the image center > > or the edges than it simple does not fit to what I get in the > > fft-module. > > > > when reading the data point from selection, could there be some wrong > > usage? > > I'm sorry, I didn't work with this part of Gwyddion code for some > time... Selections are *NOT* offset. They have origin in the top-left > corner, like pixel coordinates, just scaled to the physical scale. You > have to add the offsets yourself: > > sel[0] += gwy_data_field_get_xoffset(data_field); > sel[1] += gwy_data_field_get_yoffset(data_field); > > This is, again, for compatibility reasons because offsets were a kind of > afterthought. > > Regards, > > Yeti > > > ------------------------------------------------------------------------------ > Want excitement? > Manually upgrade your production database. > When you want reliability, choose Perforce. > Perforce version control. Predictably reliable. > http://pubads.g.doubleclick.net/gampad/clk?id=157508191&iu=/4140/ostg.clktrk > _______________________________________________ > Gwyddion-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/gwyddion-users ------------------------------------------------------------------------------ Want excitement? Manually upgrade your production database. When you want reliability, choose Perforce. Perforce version control. Predictably reliable. http://pubads.g.doubleclick.net/gampad/clk?id=157508191&iu=/4140/ostg.clktrk _______________________________________________ Gwyddion-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/gwyddion-users
