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ProjectMD v1

Summary

Sum a MDHistoWorkspace along a choosen dimension

See Also

CutMD, BinMD

Properties

Name	Direction	Type	Default	Description
InputWorkspace	Input	IMDHistoWorkspace	Mandatory
ProjectDirection	Input	string	Z	The project direction. Allowed values: [‘X’, ‘Y’, ‘Z’, ‘K’]
StartIndex	Input	number	0
EndIndex	Input	number	-1
OutputWorkspace	Output	Workspace	Mandatory

Description

ProjectMD reduces the dimensionality of a MHDistoWorkspace by summing it along a specified dimension. Example: you have a 3D MDHistoWorkspace with X,Y,TOF. You sum along Z (TOF) and the result is a 2D workspace X,Y which gives you a detector image.

Besides the obvious input and output workspaces you have to specify the dimension along which you wish to sum. The following code is used:

X

Dimension 0

Y

Dimension 1

Z

Dimension 2

K

Dimension 3

The summation range also has to be specified. This is in indices into the appropriate axis.

Usage

Example - Summing a couple of dimensions

def outputMDDimensions(ws):
    num_dims = ws.getNumDims()
    print("Name   Bins   Min     Max")
    for dim_index in range(num_dims):
        dim = ws.getDimension(dim_index)
        print("{}      {}      {:.2f}   {:.2f}".format(
              dim.name, dim.getNBins(), dim.getMinimum(), dim.getMaximum()))

#create a test MD event workspace
mdew = CreateMDWorkspace(Dimensions=3, Extents=[-1,1,-5,5,-9,10],
    Names='A, B, C', Units='U, U, U')
FakeMDEventData(mdew, PeakParams=[100000, 0, 0, 0, 1])

#convert to a MDHisto workspace suing BinMD
wsHisto = BinMD(mdew,AlignedDim0='A,-1,1,9',
    AlignedDim1='B,-5,5,5',
    AlignedDim2='C,-9,10,9')

print("The original workspace")
outputMDDimensions(wsHisto)

wsProjected1 = ProjectMD(wsHisto,ProjectDirection="Z")
print("\nAfter the workspace has been summed in the Z direction")
outputMDDimensions(wsProjected1)

wsProjected2 = ProjectMD(wsProjected1,ProjectDirection="X")
print("\nAfter the workspace has been also been summed in the X direction")
outputMDDimensions(wsProjected2)

The original workspace
Name   Bins   Min     Max
A      9      -1.00   1.00
B      5      -5.00   5.00
C      9      -9.00   10.00

After the workspace has been summed in the Z direction
Name   Bins   Min     Max
A      9      -1.00   1.00
B      5      -5.00   5.00

After the workspace has been also been summed in the X direction
Name   Bins   Min     Max
B      5      -5.00   5.00

Categories: AlgorithmIndex | MDAlgorithms\Slicing

Source

C++ header: ProjectMD.h

C++ source: ProjectMD.cpp