DakotaChiSquared v1

../_images/DakotaChiSquared-v1_dlg.png

DakotaChiSquared dialog.

Properties

Name Direction Type Default Description
DataFile Input string Mandatory Input Nexus file containing data. Allowed extensions: [‘.nxs’]
CalculatedFile Input string Mandatory Input Nexus file containing calculated data. Allowed extensions: [‘.nxs’]
OutputFile Input string Mandatory Output filename containing chi^2. Allowed extensions: [‘.xml’]
ChiSquared Output number    
ResidualsWorkspace Output MatrixWorkspace   The name of the workspace that will contain residuals.

Description

Compare two nexus files containing matrix workspaces and output chi squared into a file for use with the Dakota program.

Usage

#We need to create some files
import mantid,os.path
datafile=os.path.join(mantid.config.getString('defaultsave.directory'),'DakotaChiSquared_data.nxs')
simfile=os.path.join(mantid.config.getString('defaultsave.directory'),'DakotaChiSquared_sim.nxs')
chifile=os.path.join(mantid.config.getString('defaultsave.directory'),'DakotaChiSquared_chi.txt')

CreateWorkspace(OutputWorkspace='data',DataX='1,2,3,4,5',DataY='1,0,1,4,4',DataE='1,1,1,2,2')
CreateWorkspace(OutputWorkspace='sim',DataX='1,2,3,4,5',DataY='1,1,1,1,1',DataE='0,0,0,0,0')
SaveNexus('data',datafile)
SaveNexus('sim',simfile)

#clean up the workspaces
DeleteWorkspace("data")
DeleteWorkspace("sim")

#run the algorithm
result=DakotaChiSquared(datafile,simfile,chifile)

#Test to see if everything is ok
print "Chi squared is ",result[0]
print "Residuals are ", result[1].dataY(0)
#and the content of the file
f = open(chifile,'r')
chistr=f.read()
print "Content of the file : ",chistr.strip()
f.close()
Chi squared is  5.5
Residuals are  [ 0.  -1.   0.   1.5  1.5]
Content of the file :  5.5 obj_fn

Categories: Algorithms | Utility\Workspaces