4.0

SliceMDHisto v1

../_images/SliceMDHisto-v1_dlg.png

SliceMDHisto dialog.

Summary

Extracts a hyperslab of data from a MDHistoWorkspace

Properties

Name Direction Type Default Description
InputWorkspace Input IMDHistoWorkspace Mandatory  
Start Input int list   A comma separated list of min,for each dimension
End Input int list   A comma separated list of max for each dimension
OutputWorkspace Output IMDHistoWorkspace Mandatory  

Description

SliceMDHisto extracts a hyperslab of data from a MDHistoWorkspace. Beyond the usual input and output workspace parameters, the start and end of the hyperslabs dimensions are required. Both as comma separated lists with an entry for each dimension of the MDHistoWorkspace.

Example: consider an input MDHistoWorkspace with dimensions 100,100,100. Running SliceMDHisto with parameters Start= 20,20,20 and End= 50,50,100 will copy all the data between x: 20-50, y: 20-50, z:20-100 into the result MDHistoWorkspace with dimensions 30,30,80.

For a more up-to-date way of performing slices on a MDHistoWorkspace this see IntegrateMDHistoWorkspace v1

Usage

Example - Taking an MDHisto slice

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)

#The values in start and end are the Bin numbers(staring at 0) of the dimensions
wsOut = SliceMDHisto(wsHisto,Start=[1,2,0],End=[7,4,7])

print("\nAfter Slicing")
outputMDDimensions(wsOut)

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 Slicing
Name   Bins   Min     Max
A      6      -0.78   0.56
B      2      -1.00   3.00
C      7      -9.00   5.78

Categories: Algorithm Index | MDAlgorithms\Slicing

Source

C++ source: SliceMDHisto.cpp (last modified: 2018-10-05)

C++ header: SliceMDHisto.h (last modified: 2018-10-05)