3.5

PlusMD v1

../_images/PlusMD-v1_dlg.png

PlusMD dialog.

Summary

Sum two MDHistoWorkspaces or merges two MDEventWorkspaces together by combining their events together in one workspace.

Properties

Name Direction Type Default Description
LHSWorkspace Input IMDWorkspace Mandatory An MDEventWorkspace, MDHistoWorkspace or WorkspaceSingleValue as the left-hand side of the operation.
RHSWorkspace Input IMDWorkspace Mandatory An MDEventWorkspace, MDHistoWorkspace or WorkspaceSingleValue as the right-hand side of the operation.
OutputWorkspace Output IMDWorkspace Mandatory Name of the output MDEventWorkspace or MDHistoWorkspace.

Description

This algorithm sums two MDHistoWorkspaces or merges two MDEventWorkspaces together.

MDHistoWorkspaces

  • MDHistoWorkspace + MDHistoWorkspace
    • The operation is performed element-by-element.
  • MDHistoWorkspace + Scalar or Scalar + MDHistoWorkspace
    • The scalar is subtracted from every element of the MDHistoWorkspace. The squares of errors are summed.

MDEventWorkspaces

This algorithm operates similary to calling Plus on two EventWorkspaces: it combines the events from the two workspaces together to form one large workspace.

Note for file-backed workspaces

The algorithm uses CloneMDWorkspace v1 to create the output workspace, except when adding in place (e.g. A = A + B ). See CloneMDWorkspace v1 for details, but note that a file-backed MDEventWorkspace will have its file copied.

  • If A is in memory and B is file-backed, the operation C = A + B will clone the B file-backed workspace and add A to it.
  • However, the operation A = A + B will clone the A workspace and add B into memory (which might be too big!)

Also, be aware that events added to a MDEventWorkspace are currently added in memory and are not cached to file until SaveMD v2 or another algorithm requiring it is called. The workspace is marked as ‘requiring file update’.

Categories: Algorithms | MDAlgorithms | MDArithmetic

Source

C++ source: PlusMD.cpp

C++ header: PlusMD.h