Help with Topas - beginner level

danac

Hello everyone,

I am trying to learn Topas (at least the basic functions) and I have encountered an error that I cannot solve. I want to learn how to do peak fitting and indexing and when I run the script from Jedit in Topas, I get the following error:

"Error loading sstring_in
at LINE 33
See log file C:\Topas-5\topas.log
Cannot locate bkg from circles_prm in data structures"

Could anyone help me with any information?

Kind regards,
Dana

johnsoevans

There are lots of tutorials at http://community.dur.ac.uk/john.evans/topas_workshop/topas_user_menu.htm. Along with the topas tech ref, they should give you an idea of the inp file structure. The error you have looks like a keyword in the wrong part of the file. E.g. Specifying a bkg outside an xdd section.

danac

Thank you for the reply. I am using those exact tutorials to learn :). You were right, there was a text in the wrong part of the file.
I was able to run it, but now I get the following message:

" Number of independent parameters : 27
0 Time 0.05 Rwp 37671.935 0.000 MC 0.00 0
Sparse matrix methods invoked - 78.2% of the A matrix elements are zero
Abnormal in refinement - please contact the author"

rowlesmr

Not very much to add, but the Rwp value is quite large, so your model is probably starting a long way from the best solution. If you manually alter some of the parameter values to better ones, that might help the refinement.

.

On the other hand, I've never seen that error before, and I've seen a lot!

katarinac

I'm in the same research group as Dana, and have performed the indexing without any problems on another computer. When I tried to do the same on the computer in question (same input/data), the same error appeared... could it be a program error?

rowlesmr

Hi Katarina

Same data, different computer, different installation of Topas?

Have you tried reinstalling Topas? Someone may have changed something in topas.inc, or something else may have glitched.

Matthew

katarinac

Hi Matthew,

Same data, different computer... and yes, two different TOPAS programmes.

We haven't tried re-installing, definitely worth a try. Thank you!

Katarina