Implement xtype other than tth

[yucongalicechen]

closes #45

I implemented functions to allow corrections on grid other than tth. The edits include:

• In the main module, replace all "tth" with args.xtype.
• In the tools module, filter out invalid xtype or set args.xtype to "tth" or "q" based on inputs (this makes it easy to write the output files using the dump function).
• In compute_cve function in functions.py, interpolate cve_do we get from the global tth to the input grid.

Question: I didn't see functions that allow transfer between tth and d, so when xtype=d do we simply put xtype=tth?
@sbillinge ready for some feedback.

[sbillinge]

Question: I didn't see functions that allow transfer between tth and d, so when xtype=d do we simply put xtype=tth? @sbillinge ready for some feedback.

@yucongalicechen this still needs to be implemented in diffraction_objects. Please could you make an issue if it is not already there? d = 2*pi/Q.

[sbillinge]

this looks good. It may need a test for when an invalid input is provided for xtype. This can go in a separate test test_set_xtype_bad

[sbillinge]

@yucongalicechen this code is very high quality. Great job! you have learned well!

[yucongalicechen]

Here's the test function for bad cases :)

[yucongalicechen]

Question: I didn't see functions that allow transfer between tth and d, so when xtype=d do we simply put xtype=tth? @sbillinge ready for some feedback.

@yucongalicechen this still needs to be implemented in diffraction_objects. Please could you make an issue if it is not already there? d = 2*pi/Q.

@sbillinge
Sounds good, I’ll add an issue in diffpy.utils.
A related question is that the dump function only writes tth and q - do we want to add q as well?
Another related question - I think we would like to have a function in diffpy.utils that interpolate DOs (as described in #94). Is this the issue here (diffpy/diffpy.utils#48), or shall I open another issue for this?

[sbillinge]

Question: I didn't see functions that allow transfer between tth and d, so when xtype=d do we simply put xtype=tth? @sbillinge ready for some feedback.

@yucongalicechen this still needs to be implemented in diffraction_objects. Please could you make an issue if it is not already there? d = 2*pi/Q.

@sbillinge Sounds good, I’ll add an issue in diffpy.utils. A related question is that the dump function only writes tth and q - do we want to add q as well? Another related question - I think we would like to have a function in diffpy.utils that interpolate DOs (as described in #94). Is this the issue here (diffpy/diffpy.utils#48), or shall I open another issue for this?

yes, an issue for a user-supplied master-grid is already there i think. Yes, dump dumping d might be nice