Add patch to correct for missing SEQ_NUM keyword

metis_l1_prep.pro

@@ -331,6 +331,19 @@ pro metis_l1_prep
 	empty_params = !null
 
 	if datatype eq 0 or datatype eq 3 or datatype eq 5 then begin
+		
+		; patch to fix the lack of the keyword SEQ_NUM
+		
+		pol_id = fxpar(primary_header, 'POL_ID', missing = 0)
+		if pol_id ge 1 and pol_id le 4 then begin
+			seq_num = fxpar(primary_header, 'SEQ_NUM', missing = 0)
+			if seq_num eq 0 then begin
+				obj_cnt = fxpar(primary_header, 'OBJ_CNT')
+				n_pol = fxpar(primary_header, 'N_POL', missing = 4)
+				seq_num = ((obj_cnt - 1)/n_pol + 1)
+				fxaddpar, primary_header, 'SEQ_NUM', seq_num, before = 'POL_ID'
+			endif
+		endif
 
 		; NOTE - DACPOL parameters are not calibrated since a calibration curve does not exist in the IDB. Their calibration in physical units (e.g., voltages or angles) should be done later