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Table of Contents
Creates a new GroupingWorkspace using an instrument from one of: an input workspace, an instrument name, or an instrument IDF file. Optionally uses bank names to create the groups.
Name | Direction | Type | Default | Description |
---|---|---|---|---|
InputWorkspace | Input | MatrixWorkspace | Optional: An input workspace with the instrument we want to use. | |
InstrumentName | Input | string | Optional: Name of the instrument to base the GroupingWorkspace on which to base the GroupingWorkspace. | |
InstrumentFilename | Input | string | Optional: Path to the instrument definition file on which to base the GroupingWorkspace. Allowed extensions: [‘.xml’] | |
OldCalFilename | Input | string | Optional: Path to the old-style .cal grouping/calibration file (multi-column ASCII). You must also specify the instrument. Allowed extensions: [‘.cal’] | |
GroupNames | Input | string | Optional: A string of the instrument component names to use as separate groups. Use / or , to separate multiple groups. If empty, then an empty GroupingWorkspace will be created. | |
GroupDetectorsBy | Input | string | Only used if GroupNames is empty. Allowed values: [‘’, ‘All’, ‘Group’, ‘2_4Grouping’, ‘Column’, ‘bank’] | |
MaxRecursionDepth | Input | number | 5 | Number of levels to search into the instrument (default=5) |
FixedGroupCount | Input | number | 0 | Used to distribute the detectors of a given component into a fixed number of groups |
CustomGroupingString | Input | string | This takes a comma separated list of grouped detector IDs. An example of the syntax is 1,2+3,4-6,7:10. The documentation page for this algorithm gives a full explanation of this syntax. | |
ComponentName | Input | string | Specify the instrument component to group into a fixed number of groups | |
OutputWorkspace | Output | GroupingWorkspace | An output GroupingWorkspace. | |
NumberGroupedSpectraResult | Output | number | The number of spectra in groups | |
NumberGroupsResult | Output | number | The number of groups |
A GroupingWorkspace
is a simple workspace with one value per
detector pixel; this value corresponds to the group number that will
be used when focussing or summing another workspace.
This algorithm creates a blank GroupingWorkspace
. It uses the
InputWorkspace
, InstrumentName
, OR InstrumentFilename
parameter to determine which Instrument to create.
If the OldCalFilename
parameter is given, the .cal
ASCII file
will be loaded to fill the group data.
If the GroupNames parameter
is given, the names of banks matching
the comma-separated strings in the parameter will be used to
sequentially number the groups in the output.
If both the FixedGroupCount
and ComponentName
parameter are
given then the detectors for the given component will be grouped into
the number of groups specified, detectors will be left ungrouped in
the event that the number of detectors does not divide equally into
the number of groups.
If both the CustomGroupingString
and ComponentName
property are
given, then the detectors for the given component will be grouped using
this grouping string. The syntax of the CustomGroupingString
is the
same as used in the GroupDetectors algorithm,
and is explained below:
An example CustomGroupingString is 1,2+3,4-6,7:10
The comma ',' separator denotes the different groups.
The plus '+' separator means the adjoining detector IDs will be put in the same group.
The dash '-' separator means the detector IDs inclusive to this range will be put in the same group.
The colon ':' separator means the detector IDs inclusive to this range will be put in their own individual groups.
The CustomGroupingString 1,2+3,4-6,7:10 therefore has the following detector grouping:
Group 1: 1
Group 2: 2 3
Group 3: 4 5 6
Group 4: 7
Group 5: 8
Group 6: 9
Group 7: 10
GroupDetectorsBy
has five options
All
create one group for the whole instrumentbank
Creates one group per instrument component that starts with the word bank
Group
Creates one group per instrument component that starts with the word Group
. POWGEN will create groups for North
and South
. SNAP will create groups for East
and West
.Column
Creates one group per instrument component that starts with the word Column
2_4Grouping
(SNAP only) creates one group of 4 columns of SNAP detectors and another with the remaining 2 columns. This grouping is used frequently in their reduction.Example - CreateGroupingWorkspace for MUSR Instrument
Note
To run these usage examples please first download the usage data, and add these to your path. In Mantid this is done using Manage User Directories.
# Run algorithm with instrument specified
result = CreateGroupingWorkspace(InstrumentName="MUSR")
# Confirm instrument in grouping workspace.
grouping = result[0]
inst1 = grouping.getInstrument()
comp1 = inst1.getComponentByName("MUSR")
print("Instrument name = {}".format(comp1.getName()))
Output:
Instrument name = MUSR
Example - CreateGroupingWorkspace from MUSR workspace
# Create Workspace
load_result = Load("MUSR00015189")
group = load_result[0]
ws_1 = group[0]
# Run algorithm with workspace
result = CreateGroupingWorkspace(InputWorkspace=ws_1)
# Confirm instrument in grouping workspace.
grouping = result[0]
inst1 = grouping.getInstrument()
comp1 = inst1.getComponentByName("MUSR")
print("Instrument name = {}".format(comp1.getName()))
Output:
Instrument name = MUSR
Example - CreateGroupingWorkspace from GEM Instrument Definition
# Run algorithm with Instrument Definition File
result = CreateGroupingWorkspace(InstrumentFilename="GEM_Definition.xml")
# Confirm instrument in grouping workspace.
grouping = result[0]
inst1 = grouping.getInstrument()
comp1 = inst1.getComponentByName("GEM")
print("Instrument name = {}".format(comp1.getName()))
Output:
Instrument name = GEM
Example - CreateGroupingWorkspace for IRIS graphite component
grouping_ws, spectra_count, group_count = CreateGroupingWorkspace(InstrumentName='IRIS', ComponentName='graphite', FixedGroupCount=5)
print("Number of grouped spectra: {}".format(spectra_count))
print("Number of groups: {}".format(group_count))
Output:
Number of grouped spectra: 50
Number of groups: 5
Example - CreateGroupingWorkspace using a CustomGroupingString
grouping_ws, spectra_count, group_count = CreateGroupingWorkspace(InstrumentName='IRIS', ComponentName='graphite', CustomGroupingString='3-25,26,27+28,29-35,36:53')
print("Number of grouped spectra: {}".format(spectra_count))
print("Number of groups: {}".format(group_count))
Output:
Number of grouped spectra: 51
Number of groups: 22
Categories: AlgorithmIndex | Utility\Workspaces | Transforms\Grouping
C++ header: CreateGroupingWorkspace.h (last modified: 2021-03-31)
C++ source: CreateGroupingWorkspace.cpp (last modified: 2021-03-31)