SANSMove v1

../_images/SANSMove-v1_dlg.png

SANSMove dialog.

Summary

Moves SANS workspaces.

Properties

Name Direction Type Default Description
SANSState Input Dictionary   A property manager which fulfills the SANSState contract.
Workspace InOut MatrixWorkspace Mandatory The sample scatter workspace. This workspace does not contain monitors.
MoveType Input string ElementaryDisplacement The type of movement. This can be: 1) InitialMove for freshly workspaces, 2) ElementaryDisplacement of the instrument component, 3) SetToZero resets a component to the initial position. Allowed values: [‘InitialMove’, ‘ElementaryDisplacement’, ‘SetToZero’]
BeamCoordinates Input dbl list   The coordinates which are used to position the instrument component(s). If nothing is specified, then the coordinates from SANSState are used
Component Input string   Component that should be moved.
IsTransmissionWorkspace Input boolean False If the input workspace is a transmission or direct workspace

Description

This algorithm moves a SANS workspace according to the settings in the state object. Additionally the user can specify the beam centre. Note that if the beam centre is also specified in the state object, then the manual selection takes precedence. The way we perform a move is highly-instrument and in fact data-dependent. Currently the move mechanism is implemented for SANS2D, LOQ and LARMOR.

Relevant SANSState entries for SANSMove

The required information for the move operation is retrieved from a state object. It contains information which is specific to each instrument and to the specific IDF.

Common elements of the move state object are:

Entry Type Description Mandatory Default value
sample_offset Float The offset of the sample in m No 0.0
sample_offset_direction CanonicalCoordinates enum The direction of the sample offset No CanonicalCoordinates.Z
detectors Dict Dictionary of detectors. auto setup auto setup
monitor_names Dict A dictionary with monitor index vs monitor name auto setup auto setup

The detectors dictionary above maps to a state object for the individual detectors:

Entry Type Description Mandatory Default value
x_translation_correction Float X translation for the detector in m No 0.0
y_translation_correction Float Y translation for the detector in m No 0.0
z_translation_correction Float X translation for the detector in m No 0.0
rotation_correction Float Rotation correction for the detector in degrees No 0.0
side_correction Float Side correction for the detector in m No 0.0
radius_correction Float Radius correction for the detector in m No 0.0
x_tilt_correction Float X tilt correction for the detector in degrees No 0.0
y_tilt_correction Float Y tilt correction for the detector in degrees No 0.0
z_tilt_correction Float Z tilt correction for the detector in degrees No 0.0
sample_centre_pos1 Float Position 1 of the beam centre in m or degree, depending on the setting No 0.0
sample_centre_pos2 Float Position 2 of the beam centre in m No 0.0
detector_name String Detector name auto setup auto setup
detector_name_short String Short detector name auto setup auto setup

The individual instruments have additional settings.

For LOQ:

Entry Type Description Mandatory Default value
         
center_position Float The centre position No 317.5 / 1000.

For SANS2D:

Entry Type Description Mandatory Default value
         
hab_detector_radius Float Radius for the front detector in m auto setup 306.0 / 1000.
hab_detector_default_sd_m Float Default sd for front detector in m auto setup
hab_detector_default_x_m Float Default x for the front detector in m auto setup 1.1
lab_detector_default_sd_m Float Default sd for the rear detector in m auto setup
hab_detector_x Float X for the front detector in m auto setup
hab_detector_z Float Z for the front detector in m auto setup
hab_detector_rotation Float Rotation for the front detector auto setup
lab_detector_x Float X for the rear detector in m auto setup
lab_detector_z Float Z for the rear detector in m auto setup
monitor_4_offset Float Offset for monitor 4 No

For LARMOR

Entry Type Description Mandatory Default value
         
bench_rotation Float The angle for the bench rotation No

Note that these settings should be only populated via the GUI or the Python Interface of ISIS SANS.

Move options: InitialMove, ElementaryDisplacement, SetToZero

The InitialMove setting is relevant when loading data before a reduction. It will apply all corrections which are specified in the state object.

The ElementaryDisplacement will perform a relative translation/rotation according to the specified beam centre value.

The SetToZero places the component into the default position.

Beam Centre

The beam centre for a reduction is normally specified in the state object, but it can also be specified in manually here. If the beam centre is specified explicitly, then it is being used instead of the setting in the state object.

Categories: Algorithm Index | SANS\Move

Source

Python: SANSMove.py (last modified: 2019-01-25)