PDLoadCharacterizations v1¶

PDLoadCharacterizations dialog.

Table of Contents

Summary
Properties
Description
- Characterization File
- Characterization TableWorkspace
Source

Summary ¶

Load a characterization file used in Powder Diffraction Reduction.

Properties ¶

Name	Direction	Type	Default	Description
Filename	Input	string	Mandatory	Characterizations file. Allowed extensions: [‘.txt’]
ExpIniFilename	Input	string		(Optional) exp.ini file used at NOMAD. Allowed values: [‘ini’]
OutputWorkspace	Output	TableWorkspace	Mandatory	Output for the information of characterizations and runs
IParmFilename	Output	string		Name of the gsas instrument parameter file.
PrimaryFlightPath	Output	number		Primary flight path L1 of the powder diffractomer.
SpectrumIDs	Output	int list		Spectrum IDs (note that it is not detector ID or workspace indices). The list must be either empty or have a size equal to input workspace’s histogram number.
L2	Output	dbl list		Seconary flight (L2) paths for each detector. Number of L2 given must be same as number of histogram.
Polar	Output	dbl list		Polar angles (two thetas) for detectors. Number of 2theta given must be same as number of histogram.
Azimuthal	Output	dbl list		Azimuthal angles (out-of-plane) for detectors. Number of azimuthal angles given must be same as number of histogram.

This algorithm loads information into a TableWorkspace for the characterization information and a collection of output parameters for the focus positions to be used in EditInstrumentGeometry v1. If a section is missing then those parameters will be empty. This includes an empty table (zero rows) if that information is missing. The resulting TableWorkspace is intented to be used by PDDetermineCharacterizations v1

This algorithm is one of the workflow algorithms that helps SNSPowderReduction v1.

Characterization File ¶

An example from POWGEN shows both of the available portions of a characterization file:

Instrument parameter file:
1 3.18 90.0000
L1 60.0
#S 1 characterization runs
#L frequency(Hz) center_wavelength(angstrom) bank_num vanadium_run empty_run vanadium_back d_min(angstrom) d_max(angstrom)
60 0.533  1 17533 0 0 0.05  2.20  0000.00  16666.67
60 1.066  2 17534 0 0 0.30  4.60  8333.33  25000.00
60 1.333  3 17535 19770 0 0.43  5.40 12500.00  29166.67
60 2.665  4 17536 0 0 1.15  9.20 33333.33  50000.00
60 4.797  5 17537 0 0 2.25 15.35 66666.67  83333.67
60 3.731  6 18280 0 0 1.70 12.50 50000.00  66666.67
10 3.198  1 17538 0 0 0.05 15.40 00000.00 100000.00

The first line Instrument parameter file: must be present to mark the beginning of the first section. Whatever string appears after the semicolon is copied into the IParmFilename output property. The following lines are of the form “bank l2 polar” with the last line being the keyword L1 followed by the effective primary flight path. This information is saved in the IParmFilename, SpectrumIDs, L2, Polar, and PrimaryFlightPath properties. The Azimuthal properties is filled with zeros and is the same length as SpectrumIDs, L2, Polar, and PrimaryFlightPath.