Create SavePAR algorithm

[Stuart Campbell]

A SavePAR() algorithm along the lines of the SavePHX() algorithm.

This is a request from Garrett Granroth:

A command to Save a Par file for the current detector geometry is needed.  
This should work after a group detectors command is used to gang detectors.

[Alex Buts]

In [14668]:

refs #3640 save par saves ASCII par file but more tests are needed to be sure that it saves exactly what people expect

[Alex Buts]

In [14674]:

refs #3640 temporary blocking failing on mac test until build is fixed and permanent fix can be verified.

[Alex Buts]

In [14708]:

refs #3640 this should be all done on this ticket.

[Alex Buts]

In [14710]:

refs #3640 fixing Unix errors and warnings

[Alex Buts]

In [14713]:

refs #3640 attempt to deal with Unix error.

[Alex Buts]

In [14715]:

refs #3640 attempt to deal with Unix error.

[Alex Buts]

In [14716]:

refs #3640 attempt to deal with Unix error.

[Alex Buts]

In [14722]:

refs #3640 fixing mac error which should exhaust the opportunities, despite lexical cast can appear better.

[Alex Buts]

In [14723]:

refs #3640 big simplification -- change to lexical_cast

[Alex Buts]

should do the job. How these par files are related to par files produced by other algorithms, still should be verified.

[Stuart Campbell]

The numbers in the PAR file look close enough, I am just alittle concerned that the azimuthal angle has the opposite sign to that produced from our files.

[Stuart Campbell]

Python script to generate PAR file from NeXus files.

[Stuart Campbell]

I have attached the script we use to generate the PAR files for an ungrouped instrument. The script reads a NeXus file (you can use CNCS_7860_event.nxs in the AutoTestData directory)

[Stuart Campbell]

Created ticket #3798 for missing wiki page.

[Stuart Campbell]

Changed owner to Michael just so we can close it.

[Stuart Campbell]

Apparently, the sign change for the azimuthal angle is deliberate.

From Toby (via Alex):

/*!
*    an ASCII Tobyfit par file format:
*
*     par(6,ndet)         contents of array
*
*         1st column      sample-detector distance
*         2nd  "          scattering angle (deg)
*         3rd  "          azimuthal angle (deg)
*                     (west bank = 0 deg, north bank = -90 deg etc.)
*                     (Note the reversed sign convention cf .phx files)
*         4th  "          width (m)
*         5th  "          height (m)
*         6th  "          DetID (m)
*-----------------------------------------------------------------------
*/

[Stuart Campbell]

This ticket has been transferred to github issue ​4487