I was attempting to familiarize myself with the output of the sh2peaks command using the -direction option. I assumed that when providing ‘-direction 0 0’, (phi and theta are 0, so directing ‘upwards’) the output peak-file should only contain vectors running along the z-axis, but this is not what I observed. I guess I’m not fully comprehending this option.
Btw, are theta and phi to be expressed in radians or in degrees?
-peaks option is only use to initialise the search for the nearest peak, as hinted in the docs:
-peaks image the program will try to find the peaks that most closely match those in the image provided.
In general, the actual peak direction should be close to, but not identical to the direction provided.
If you need to sample the ODF along specific predefined directions, you can use the sh2amp command.
Just be wary: I’ve a feeling that there may be discrepancies in various parts of the code in the interpretation of polar coordinates as using inclination vs. elevation…