Implement LoTSS subtract
This MR implements the subtraction of the LoTSS 6'' skymodel required for widefield imaging in the delay calibration workflow. Given the DIS2 solutions in H5parm format, and paths to the ddf-pipeline results the user can subtract the 6'' model from the data using the subtract_lotss_model
option in the delay-calibration workflow. It subtracts outside a square, user-specifiable region (defaulting to the 2.5 deg FWHM).
After running the workflow on a 2 MHz 10 min test set, sources have indeed been subtracted: From left to right: DATA, DATA_DI_CORRECTED, subtracted DATA_DI_CORRECTED
Edited by Frits Sweijen