Extend algorithm LoadInstrumentFromNexus

[peterfpeterson]

This issue was originally TRAC 9537

This ticket is blocked by :

• TRAC9511

The current algorithm LoadInstrumentFromNexus has very limited functionality. It loads only muon Nexus files and gets only a small amount of information from it.

It can extended by taking code from algorithms that load instruments from nexus files (LoadEventNexus, CreateGroupingWorkspace, and CreateChunkingFromInstrument in http://trac.mantidproject.org/mantid/ticket/9511 are three). Each of them has very similar code that should be collected into a single workflow algorithm.

[peterfpeterson]

@KarlPalmen (2014-07-24T15:12:43):
A look at the code shows:

'''CreateChinkingFromInstrument''' first attempts to get the instrument from the workspace. If there is no workspace, it runs loadIDFFromNexus and it also reads the instrument name from Nexus separately. If it does not run LoadInstrument in the event of loadIDFFromNexus not working.

'''CreateGroupingWorkspace''' first attempts to get the instrument from the workspace. If there is no workspace, it runs LoadInstrument with either the instrument name or IDF filename. It has no nexus file.

'''LoadEventNexus''' first attempts to LoadIDFFromNexus. If that does not work, it reads the Nexus file to get the instrument name then runs LoadInstrument with the instrument name.

---

@KarlPalmen (2014-08-04T10:25:23):
LoadInstrumentFromNexus currently has no unit test. A unit test would be added in the course of work on this ticket.

[peterfpeterson]

This has been done for some time already.