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# ConvertDiffCal v1¶

## Summary¶

Convert diffraction calibration from old to new style

CalculateDIFC

## Properties¶

Name

Direction

Type

Default

Description

OffsetsWorkspace

Input

OffsetsWorkspace

Mandatory

OffsetsWorkspace containing the calibration offsets.

PreviousCalibration

Input

TableWorkspace

A calibration table used as a cache for creating the OutputWorkspace. Effectively, this algorithm applies partial updates to this table and returns it as the OutputWorkspace

OutputWorkspace

Output

TableWorkspace

Mandatory

An output workspace.

## Description¶

Generates a calibration table based on d-spacing detector offsets provided in an OffsetsWorkspace. Optionally updates detector calibrations from an existing calibration file. Each detector offset in the OffsetsWorkspace is processed as follows:

If the detector is masked, its $$DIFC$$ will not be calculated or updated.

If a PreviousCalibration entry exists for the detector, the detector entry’s $$DIFC$$ will be updated as follows and reflected in the final calibration table:

$DIFC_{new} = \frac{DIFC_{old}}{1+offset}$

If a prior calibration entry does not exist for the detector, calculate the $$DIFC$$ as follows using geometry of the experiment:

$DIFC = \frac{1}{1+offset}\frac{2m_N}{h} L_{tot} sin \theta$

If a detector is present in the PreviousCalibration table but is not found in the OffsetsWorkspace, it will be propagated to the output calibration table unchanged.

## Usage¶

Note

Example - ConvertDiffCal

The file needed for this example are not present in our standard usage data download due to its size. It be downloaded from pg3_mantid_det.cal.

LoadCalFile(InstrumentName="PG3",
CalFilename="pg3_mantid_det.cal",
MakeGroupingWorkspace=False,
MakeOffsetsWorkspace=True,