MuonPreProcess dialog.
Table of Contents
Perform a series of common analysis pre-processing steps on Muon data. Sample logs are modified to record the input parameters.
| Name | Direction | Type | Default | Description |
|---|---|---|---|---|
| InputWorkspace | Input | Workspace | Mandatory | Input workspace containing data from detectors that the grouping/pairing will be applied to. |
| OutputWorkspace | Output | WorkspaceGroup | Mandatory | The output workspace group with all corrections applied. For single period data, a group is returned with a single workspace. |
| TimeMin | Input | number | Optional | Start time for the data in micro seconds. |
| TimeMax | Input | number | Optional | End time for the data in micro seconds. |
| RebinArgs | Input | dbl list | Parameters used for rebinning. If empty - rebinning is not done. | |
| TimeOffset | Input | number | Optional | Shift the times of all data by a fixed amount (in micro seconds). The value given corresponds to the bin that will become 0.0 seconds. |
| DeadTimeTable | Input | TableWorkspace | TableWorkspace with dead time information, used to apply dead time correction. |
When interacting with the Muon Analysis (old) interface, operations such as detector grouping, group and pair asymmetry are performed on data. As part of the workflow, several “pre-processing” steps are also necessary; such as rebinning and cropping the data, applying dead time corrections, and shifting the time axis by a fixed amount (sometimes referred to as “first good data”).
This algorithm intends to capture the common pre-processing steps, which are not muon physics specific concepts, and apply them all at once to produce data which is ready for the muon-specific operations. This way, scripting the workflows of the Muon Analysis (old) interface is much more intuitive and simple.
As indicated in the input variable names to this algorithm; there are four distinct operations applied to the input data. In order of application these are;
The InputWorkspace can be a single workspace object, and multi period data is supported by supplying a WorkspaceGroup as the input workspace, where each workspace within the group represents a single period.
The OutputWorkspace is always a Workspace Group; for single period data the group only contains a single workspace. The reason for this is so that the muon algorithms MuonGroupingCounts, MuonGroupingAsymmetry and MuonPairingAsymmetry can expect a consistent input between single and multi period data, and where single period data is just a limiting case of multi period data.
The four operations listed above correspond to a run of ApplyDeadTimeCorr v1, ChangeBinOffset v1, CropWorkspace v1 and Rebin v1 respectively; and so the documentation of these algorithms can be consulted for more detailed discussion of precisely how the operations are applied.
As already mentioned; the output of this algorithm can (and is intended to be) fed into one of the following algorithms;
Note
To run these usage examples please first download the usage data, and add these to your path. In MantidPlot this is done using Manage User Directories.
Note
For examples of applying custom dead times, please refer to ApplyDeadTimeCorr v1 documentation.
For examples of applying custom rebinning, please refer to Rebin v1 documentation.
Example - The output is always a WorkspaceGroup
# Single period data
dataX = [0, 1, 2, 3, 4, 5]
dataY = [10, 20, 30, 20, 10]
input_workspace = CreateWorkspace(dataX, dataY)
output_workspace = MuonPreProcess(InputWorkspace=input_workspace)
print("Input workspace is a {}".format(input_workspace.id()))
print("Output workspace is a {}".format(output_workspace.id()))
print("X values are : {}".format(output_workspace[0].readX(0)))
print("Y values are : {}".format(output_workspace[0].readY(0)))
Output:
Input workspace is a Workspace2D
Output workspace is a WorkspaceGroup
X values are : [ 0. 1. 2. 3. 4. 5.]
Y values are : [ 10. 20. 30. 20. 10.]
Example - Applying only a time offset
dataX = [0, 1, 2, 3, 4, 5]
dataY = [10, 20, 30, 20, 10]
input_workspace = CreateWorkspace(dataX, dataY)
output_workspace = MuonPreProcess(InputWorkspace=input_workspace,
TimeOffset=0.5)
print("X values are : {}".format(output_workspace[0].readX(0)))
print("Y values are : {}".format(output_workspace[0].readY(0)))
Output:
X values are : [ 0.5 1.5 2.5 3.5 4.5 5.5]
Y values are : [ 10. 20. 30. 20. 10.]
Example - Applying only a rebin
dataX = [0, 1, 2, 3, 4, 5]
dataY = [10, 20, 30, 20, 10]
input_workspace = CreateWorkspace(dataX, dataY)
output_workspace = MuonPreProcess(InputWorkspace=input_workspace,
RebinArgs=2)
print("X values are : {}".format(output_workspace[0].readX(0)))
print("Y values are : {}".format(output_workspace[0].readY(0)))
Output:
X values are : [ 0. 2. 4. 5.]
Y values are : [ 30. 50. 10.]
Example - Applying only a crop
dataX = [0, 1, 2, 3, 4, 5]
dataY = [10, 20, 30, 20, 10]
input_workspace = CreateWorkspace(dataX, dataY)
output_workspace = MuonPreProcess(InputWorkspace=input_workspace,
TimeMin=2,
TimeMax=4)
print("X values are : {}".format(output_workspace[0].readX(0)))
print("Y values are : {}".format(output_workspace[0].readY(0)))
Output:
X values are : [ 2. 3. 4.]
Y values are : [ 30. 20.]
Example - Applying only a dead time correction
dataX = [0, 1, 2, 3, 4, 5] * 4
dataY = [100, 200, 300, 200, 100] * 4
input_workspace = CreateWorkspace(dataX, dataY, NSpec=4)
# dead time correction requires the number of good frames to be set
AddSampleLog(Workspace=input_workspace, LogName="goodfrm", LogText="1")
# create the dead time table
dead_times = CreateEmptyTableWorkspace()
dead_times.addColumn("int", "spectrum", 0)
dead_times.addColumn("float", "dead-time", 0)
[dead_times.addRow([i + 1, 0.5]) for i in range(4)]
output_workspace = MuonPreProcess(InputWorkspace=input_workspace,
DeadTimeTable=dead_times)
print("X values are : {}".format(output_workspace[0].readX(0)))
print("Y values are : {}".format(output_workspace[0].readY(0).round(1)))
Output:
X values are : [ 0. 1. 2. 3. 4. 5.]
Y values are : [ 100.3 201.2 302.8 201.2 100.3]
Categories: AlgorithmIndex | Muon\DataHandling
C++ source: MuonPreProcess.cpp (last modified: 2019-06-05)
C++ header: MuonPreProcess.h (last modified: 2019-10-28)