ERROR: No algorithm ‘AlignComponents’ version ‘1’, skipping directive

Description¶

This algorithm will take a calibration in the form of a diffractioncalibration workspace from the output of for example GetDetOffsetsMultiPeaks v1 or CalibrateRectangularDetectors v1 and minimize the difference between the DIFC of the instrument and calibration workspace by moving and rotating instrument components.

The resulting calibrated geometry can be exported by ExportGeometry v1.

ComponentList¶

The ComponentList can include any instrument component that can be moved and rotated by MoveInstrumentComponent v1 and RotateInstrumentComponent v1. For example in POWGEN you can list bank46 or Column4 (which includes banks 42-46) or Group3 (which all the banks in Column 3 and 4). In the case of a component group it is treated as one object and not individual banks. In some instruments you can also specify individual tubes or pixel, e.g. bank20/tube3 and bank20/tube3/pixel7, although that is not the intention of the algorithm. You can list multiple components which will be refined in turn (e.g. in the Align the Y rotation of bank26 and bank46 in POWGEN usage example below).

Masking¶

The only masking that is on taken into account when minimising the difference in DIFC is the masking in the workspace of the MaskWorkspace property of AlignComponents.

Fitting Sample/Source¶

When fitting the sample or source position it uses the entire instrument and moves in the directions that you select. All rotation options are ignored. You can use a masking workspace to mask part of the instrument you don’t want to use to align the sample/source position (e.g. in the Align sample position in POWGEN usage example below).

The source and sample positions (in that order) are aligned before an components are aligned.

Usage¶

Example - Align the X and Z position of bank26 in POWGEN:

LoadCalFile(InstrumentName="PG3",
      CalFilename="PG3_golden.cal",
      MakeGroupingWorkspace=False,
      MakeOffsetsWorkspace=True,
      MakeMaskWorkspace=True,
      WorkspaceName="PG3")
ws = LoadEmptyInstrument(Filename="POWGEN_Definition_2015-08-01.xml")
component="bank26"
print "Start position is",ws.getInstrument().getComponentByName(component).getPos()
AlignComponents(CalibrationTable="PG3_cal",
        Workspace=ws,
        MaskWorkspace="PG3_mask",
        Xposition=True, ZPosition=True,
        ComponentList=component)
ws=mtd['ws']
print "Final position is",ws.getInstrument().getComponentByName(component).getPos()

Output:

Start position is [1.54436,0.863271,-1.9297]
Final position is [1.50591,0.863271,-1.92734]

Example - Align the Y rotation of bank26 and bank46 in POWGEN:

LoadCalFile(InstrumentName="PG3",
      CalFilename="PG3_golden.cal",
      MakeGroupingWorkspace=False,
      MakeOffsetsWorkspace=True,
      MakeMaskWorkspace=True,
      WorkspaceName="PG3")
ws = LoadEmptyInstrument(Filename="POWGEN_Definition_2015-08-01.xml")
components="bank26,bank46"
bank26Rot = ws.getInstrument().getComponentByName("bank26").getRotation().getEulerAngles()
bank46Rot = ws.getInstrument().getComponentByName("bank46").getRotation().getEulerAngles()
print "Start bank26 rotation is [{:.3f}.{:.3f},{:.3f}]".format(bank26Rot[0], bank26Rot[1], bank26Rot[2])
print "Start bank46 rotation is [{:.3f}.{:.3f},{:.3f}]".format(bank46Rot[0], bank46Rot[1], bank46Rot[2])
AlignComponents(CalibrationTable="PG3_cal",
        Workspace=ws,
        MaskWorkspace="PG3_mask",
        EulerConvention="YZX",
        AlphaRotation=True,
        ComponentList=components)
ws=mtd['ws']
bank26Rot = ws.getInstrument().getComponentByName("bank26").getRotation().getEulerAngles()
bank46Rot = ws.getInstrument().getComponentByName("bank46").getRotation().getEulerAngles()
print "Final bank26 rotation is [{:.3f}.{:.3f},{:.3f}]".format(bank26Rot[0], bank26Rot[1], bank26Rot[2])
print "Final bank46 rotation is [{:.3f}.{:.3f},{:.3f}]".format(bank46Rot[0], bank46Rot[1], bank46Rot[2])

Output:

Start bank26 rotation is [-24.061.0.120,18.016]
Start bank46 rotation is [-41.092.0.061,17.795]
Final bank26 rotation is [-25.226.0.120,18.016]
Final bank46 rotation is [-37.397.0.061,17.795]

Example - Align sample position in POWGEN:

LoadCalFile(InstrumentName="PG3",
      CalFilename="PG3_golden.cal",
      MakeGroupingWorkspace=False,
      MakeOffsetsWorkspace=True,
      MakeMaskWorkspace=True,
      WorkspaceName="PG3")
# Mask banks that don't have calibration data
MaskBTP(Workspace='PG3_mask', Instrument='POWGEN',
        Bank='22-25,42-45,62-66,82-86,102-105,123,124,143,144,164,184,204')
ws = LoadEmptyInstrument(Filename="POWGEN_Definition_2015-08-01.xml")
print "Start sample position is",ws.getInstrument().getSample().getPos().getZ()
AlignComponents(CalibrationTable="PG3_cal",
      Workspace=ws,
      MaskWorkspace="PG3_mask",
      FitSamplePosition=True,
      Zposition=True)
print "Final sample position is {:.5f}".format(mtd['ws'].getInstrument().getSample().getPos().getZ())

Output:

Start sample position is 0.0
Final sample position is 0.02826

ERROR: No algorithm ‘AlignComponents’ version ‘1’, skipping directive