The simplest way to merge two spectra is the CONTADD command, which is described above. The MERGE command merges two stack polarization spectra (that may or may not overlap) and uses a weighted mean on data with -values common to both spectra. The WMERGE command works on spectra that have the same -array (spectra can be remapped using the GRID and CONTADD commands) and produces a weighted mean of the two spectra.