Bugs: combine_spectra
Bugs
Incorrect NUMGRP and NUMELT keywords
The addresp tool is not updating the NUMGRP nor the NUMELT keywords in the output file to match the actual values in the MATRIX's N_GRP and N_CHAN columns. It is simply copying those keywords from the 1st file to the output file. These incorrect values have shown to cause problems with XSPEC v 12.11.0.