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PDDetermineCharacterizations v1¶

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Summary ¶

Determines the characterizations of a workspace.

Properties ¶

Name	Direction	Type	Default	Description
InputWorkspace	Input	MatrixWorkspace		Workspace with logs to help identify frequency and wavelength
Characterizations	Input	TableWorkspace		Table of characterization information
ReductionProperties	Input	string	__pd_reduction_properties	Property manager name for the reduction
BackRun	Input	int list	0	Empty container run to use. 0 to use value in table, -1 to not use.
NormRun	Input	int list	0	Normalization run to use. 0 to use value in table, -1 to not use.
NormBackRun	Input	int list	0	Normalization background run to use. 0 to use value in table, -1 to not use.
EmptyEnv	Input	int list	0	Empty sample environment run to use. 0 to use value in table, -1 to not use.
EmptyInstr	Input	int list	0	Empty instrument run to use. 0 to use value in table, -1 to not use.
FrequencyLogNames	Input	str list	SpeedRequest1,Speed1,frequency,skf1.speed	Candidate log names for frequency
WaveLengthLogNames	Input	str list	LambdaRequest,lambda,skf12.lambda,BL1B:Det:TH:BL:Lambda,freq	Candidate log names for wave length

This algorithm takes an InputWorkspace and Characterizations TableWorkspace and creates a PropertyManager with the appropriate characterization runs. This is done by determining the effective accelerator frequency and center wavelength and choosing the appropriate row from the table.

This algorithm is one of the workflow algorithms that helps SNSPowderReduction v1 and its child algorithm AlignAndFocusPowder v1.

Determining Frequency and Wavelength ¶

The frequency is found by inspecting the logs (in order) SpeedRequest1, Speed1, and frequency. Whichever one has a nonzero value is used. Simlilarly, the wavelength is taken by inspecting LambdaRequest then Lambda. If either the frequency or wavelength cannot be determined, the algorithm will return a default PropertyManager with mostly zeros.

PropertyManager Contents ¶

The PropertyManager will have the following keys and values. Listed in the table is also their default values. The “Alg Property” column is what property of this algorithm is used to override what is in the table. For all of those properties, “0” is interpreted as use the information from the supplied table, “-1” is interpreted as set the value to zero in the resulting PropertyManager.

Name	Type	Default	Alg Property
frequency	double	0
wavelength	double	0
bank	integer	1
vanadium	integerarray	[0]	NormRun
vanadium_background	integerarray	[0]	NormBackRun
container	integerarray	[0]	BackRun
empty_environment	integerarray	[0]	EmptyEnv
empty_instrument	integerarray	[0]	EmptyInstr
d_min	string	“”
d_max	string	“”
tof_min	double	0
tof_max	double	0
wavelength_min	double	0
wavelength_max	double	0

In the case of extra columns existing in the TableWorkspace denoting SampleContainer information: if the SampleContainer isn’t a property on the workspace, or the value isn’t one of the column labels, the value of the container column in the supplied TableWorkspace will be used instead.

For a description of the TableWorkspace see PDLoadCharacterizations.

Categories: AlgorithmIndex | Workflow\Diffraction\UsesPropertyManager