SaveSPE v1

../_images/SaveSPE-v1_dlg.png

SaveSPE dialog.

Summary

Writes a workspace into a file the spe format.

Properties

Name Direction Type Default Description
InputWorkspace Input MatrixWorkspace Mandatory The input workspace, which must be in Energy Transfer
Filename Input string Mandatory The filename to use for the saved data. Allowed extensions: [‘.spe’]

Description

Saves the data in a workspace into a file in the ASCII ‘SPE’ format.

The units used for saving will match those of the input workspace, such that if you have the units Momentum Transfer (‘DeltaE’) then you will get a traditional SPE file, you could choose to have the units in mod Q and then it will save to an SPQ file variant.

Format of .SPE files

ndet ne ! number of workspaces and number of energy bins
### Phi Grid ! angular boundaries i.e. (ndet+1) values
ang(0) ang(1) … ang(7)
ang(8) ang(9) … ang(15)
:
:
… ang(ndet)
### Energy Grid ! Energy bin boundaries i.e. (ne+1) values
en(0) en(1) … en(7)
en(8) en(9) … en(15)
:
:
… en(ne)
### S(Phi,w) ! Intensities for first workspace
s(0) s(1) … s(7)
s(8) s(9) … s(15)
:
:
… s(ndet-1)
### Errors ! Standard deviation for first workspace
err(0) err(1) … err(7)
err(8) err(9) … err(15)
:
:
… err(ndet-1)
### S(Phi,w) ! Intensities for second workspace
:
:
### Errors ! Standard deviation for second workspace
:
:
… and so on until completed ndet workspaces

IMPORTANT NOTE: in the array corresponding to the signal, the number -1030 is to be interpreted as not-a-number. That is, the corresponding pixel is to be masked. Usually of course, a detector is masked, so that all the signal array corresponding to that workspace will contain -1030. The corresponding error should be zero.

Example file produced by script below

       1       9
### Phi Grid
 5.000E-01 1.500E+00
### Energy Grid
 0.000E+00 1.000E+00 2.000E+00 3.000E+00 4.000E+00 5.000E+00 6.000E+00 7.000E+00
 8.000E+00 9.000E+00
### S(Phi,w)
-1.000E+30-1.000E+30-1.000E+30-1.000E+30-1.000E+30-1.000E+30-1.000E+30-1.000E+30
-1.000E+30
### Errors
 0.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00 0.000E+00
 0.000E+00

Restrictions on the input workspace

The input workspace must contain histogram data with common binning on all spectra.

Usage

Example - Save a workspace in SPE format

#import the os path libraries for directory functions
import os

# create histogram workspace
dataX1 = [0,1,2,3,4,5,6,7,8,9] # or use dataX1=range(0,10)
dataY1 = [0,1,2,3,4,5,6,7,8] # or use dataY1=range(0,9)
dataE1 = [1,1,1,1,1,1,1,1,1] # or use dataE1=[1]*9

ws1 = CreateWorkspace(dataX1, dataY1, dataE1)

#Create an absolute path by joining the proposed filename to a directory
#os.path.expanduser("~") used in this case returns the home directory of the current user
savefile = os.path.join(os.path.expanduser("~"), "SPEFile.spe")

# perform the algorithm
SaveSPE(InputWorkspace=ws1,Filename=savefile)

print "File Exists:", os.path.exists(savefile)

Output:

File Exists: True

Categories: Algorithms | DataHandling | SPE | Inelastic

Source

C++ source: SaveSPE.cpp

C++ header: SaveSPE.h