Supurious maxima in recalculated pole figures coming from incomplete pole figures

[Emanuel Benatti]

Hi,

I'm using mtex 3.5.0 for ODF reconstruction from experimental Xray difraction Pole Figure measurements.
My problem is the following:
If I construct the ODF from the epf pole figure (epf_PF.pdf) y get spurious maxima in the center of the recalculated PF's for the same Miller indices (recPF_from_epf.pdf). The epf PF is an incomplete pole figure, corrected for background and defocussing. However if I start with a complete pole figure (completed using popLA software, wpf_PF.pdf) y get the correct recalculated pole figures (recPF_from_wpf.pdf). The erros in the second case are an order of magnitude smaller.
My guess is that the ODF routine is assuming that de missing external values of each pole figure are 0, wich immplies that there must be a maximum in the center of the other pole figures, because the cubic crystal symmery.
Is there a way to the ODF routine to discard the external values?

I also attach the raw data files (.epf, .wpf and the import script file for each one).
Regards
Emanuel

[Ralf Hielscher]

Hi Emanuel,

thank you for your post. You might want to try the following

odf = calcODF(pf,'noQuadratureWeights')

For me this solved the issue. 

By the way, I noticed that the MTEX popla interface does not correctly import the epf data file if this additional number in the 19th column is present. Currently this is interpreted as background which is obviously wrong for your data. Do you have an idea what this number means?

I simply ignored it and you also seem to have ignored it.

Ralf.

[Emanuel Benatti]

Thanks a lot. That solve my problem. Is it possible that the option you just said isn't in the documentation? Is there a way to get (or deduce) a comprehensive list of all possible arguments of a given function?

The file in the 19th column in the epf file is just the average of the 18 previous values (i.e. the average of each ring in the pole figure). As you said it must be ignored.

Thanks again.
Emanuel