ba.fit_spectrum raises KeyError for valid survey PHA files

[zanepennella]

I am encountering a reproducible KeyError at the end of ba.fit_spectrum when fitting individual BAT survey PHA files.

Importantly:

• The XSPEC fit itself runs successfully
• The spectrum is plotted
• Fit parameters are printed
• The error occurs only after fitting, when BatAnalysis attempts to store model parameters back into the BatSurvey object

[parsotat]

Hi @zanepennella , can you paste the error message that you get?

[zanepennella]

---

Exception Traceback (most recent call last)
Cell In[32], line 2
1 try:
----> 2 ba.fit_spectrum('/Users/zanepennella/BOAT_SURVEY_DATA/01126853004_surveyresult/PHA_files/GRB221009A_survey_point_20222822156.pha', batsurvey_obs[0], fit_iterations=10000)
3 except KeyError:
4 print(f"KeyError caught — fit completed for {"20222822156"}, ignoring error.")

File ~/BatAnalysis/batanalysis/batlib.py:456, in fit_spectrum(*args, **kwargs)
453 fit_TTE_spectrum(*args, **kwargs)
454 elif isinstance(args[0], Path) or isinstance(args[0], str):
455 # we are passing in a phafilename for
--> 456 fit_survey_spectrum(*args, **kwargs)
457 else:
458 raise ValueError("The inputs cannot be parsed appropriately. Please consult the documentation for "
459 "fit_TTE_spectrum or fit_survey_spectrum for the values that should be passed in.")

File ~/BatAnalysis/batanalysis/batlib.py:713, in fit_survey_spectrum(phafilename, surveyobservation, plotting, generic_model, setPars, use_cstat, fit_iterations, verbose)
708 surveyobservation.set_pointing_info(
709 pointing_id, "model_params", model_params, source_id=source_id
710 )
712 # Incorporating the model names, parameters, errors into the BatSurvey object.
--> 713 xsp.Xset.save(phafilename.stem + ".xcm")
714 xspec_savefile = phafilename.parent.joinpath(
715 phafilename.stem + ".xcm"
716 )
717 surveyobservation.set_pointing_info(
718 pointing_id, "xspec_model", xspec_savefile, source_id=source_id
719 )

File ~/miniforge3/envs/henv/heasoft/lib/python/xspec/xset.py:695, in XspecSettings.save(self, fileName, info)
692 fileName += ".xcm"
693 saveArgs.append(fileName)
--> 695 _pyXspec.doXspecCmd(saveArgs)
697 # If doXspecCmd didn't raise an exception, assume save file has
698 # been written to disk. Add a PyXspec identifier to top of file.
699
700 # The key here is the 'inplace' specifier. While iterating through
701 # the FileInput object, standard output is automatically rerouted
702 # to the file given by 'fileName'.
703 saveFile = fileinput.input(fileName, inplace=1)

Exception: Error executing command: save