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Date: Wed, 11 Sep 2002 12:41:15 -0400 From: Xiangyun Qiu [xiangyun@pa.msu.edu] Organization: Michigan State University To: rietveld_l@ill.fr Subject: One problem when replacing a histogram. Hi Dear all, I encountered one problem when doing batch GSAS refinements: When I replace the old histogram by a new one, even though all peak profile coefficents remain the same, however, diffractometer constants are reset to the value in instrument parameter files. Actually, I want to use the refined DIF constant values instead of original values in instrument parameter file. Is there a way to tell GSAS not to replace the diffractometer constants when replacing a histogram? Thanks, Xiangyun |
Date: Wed, 11 Sep 2002 21:00:09 +0200 To: rietveld_l@ill.fr From: Jonathan WRIGHT [wright@esrf.fr] Subject: Re: One problem when replacing a histogram. The simplest way is to use an instrument parameter file containing the correct values for the instrument. Having said that, the easiest way (that I found) to do batch refinements is to change the contents of the datafile and run powpref again. So instead of telling GSAS you are replacing a histogram, just change the file which has the name GSAS is looking for. (eg: set up with data.dat, the when you want to change dataset rename the file data.dat and copy the next file in line to data.dat). This avoids the need to run expedt at all, you just run powpref then genles, save off and then delete the list file and then change the datafile to start again with the next pattern. Most programs which can be started from a command line can be fooled in a similar way. HTH, Jon |
Date: Wed, 11 Sep 2002 15:17:06 -0400 From: "Brian H. Toby" [Brian.Toby@nist.gov] Organization: NIST Center for Neutron Research To: rietveld_l@ill.fr Subject: Re: One problem when replacing a histogram. >Is there a way to tell GSAS not to replace the diffractometer constants >when >replacing a histogram? In a word -- no. In addition to Jon's good suggestion -- to overwrite the file with the data file you are planning to substitute, another option is to put each refinement in a separate directory and then use the same name for each data file (provided that you did not specify a directory when you read in the file originally). One last idea is to edit the .EXP file manually. The file is specified on a line like this: HST 1 HFIL garnet.raw You can change it and then run powpref. Brian |