Resolve RTSD-265

Closes RTSD-265

applications/lofar2/model/rtdsp/firfilter.py

@@ -179,7 +179,7 @@ def design_fir_low_pass_filter(method,
     . Method 'firls' does not support zero BW at fcutoff. With single fcutoff point error occurs: 'bands must be
       monotonically nondecreasing and have width > 0'. Work around: use a very narrow band cutoffBW at fcutoff.
       The cutoffBW band has to be much smaller than the transition band transistionBW, to avoid a flattened gain
-      around fcutoff, but also not too small, to because then the cutoffGain at fcutoff is not achieved.
+      around fcutoff, but also not too small, because then the cutoffGain at fcutoff is not achieved.
       Default force cutoffBW = transistionBW / 10 for 'firls' when input cutoffBW=0. For 'remez' method the
       cutoffBW=0 effectively, without work around, because 'remez' does support single fcutoff value specification.
 
@@ -300,8 +300,8 @@ def design_fir_low_pass_filter_adjust(method,
                                       kaiserBeta=0, fs=1.0, resolution=1e-4, verbosity=1):
     """Derive FIR coefficients for low pass filter for exact fcutoff
 
-    Uses design_fir_low_pass_filter() but achieves cutoffGain at fcutoff by adjusting fpass or fstop, and
-    fpass < fcutoff < fstop.
+    Uses design_fir_low_pass_filter() but achieves cutoffGain at fcutoff by iteratively adjusting
+    fpass or fstop, and fpass < fcutoff < fstop.
 
     Input:
     . resolution: Resolution measure for frequency and for gain. It appears that at some fine resolution