fix band rms docstring and change band rms code

Author: SaraPido

sigpro/aggregations/frequency/band.py

@@ -54,10 +54,7 @@ def band_rms(amplitude_values, frequency_values, min_frequency, max_frequency):
     lower_frequency_than = frequency_values <= max_frequency
     higher_frequency_than = frequency_values >= min_frequency
 
-    selected_idx = np.ravel(np.where(np.ravel(higher_frequency_than & lower_frequency_than)))
-
-    selected_idx = [int(x) for x in selected_idx]
-
-    selected_values = np.array(amplitude_values)[selected_idx]
+    selected_idx = np.ravel(np.where(higher_frequency_than & lower_frequency_than))
+    selected_values = amplitude_values[selected_idx]
 
     return np.sqrt(np.mean(np.square(selected_values)))

sigpro/basic_primitives.py

@@ -181,9 +181,10 @@ def __init__(self, min_frequency, max_frequency):
 
 class BandRMS(primitive.FrequencyAggregation):
     """
-    BandMean primitive class.
+    BandRMS primitive class.
 
-    Filters between a high and low band and compute the mean value for this specific band.
+    Filter between a high and low band (inclusive) and compute the rms value for this
+    specific band.
 
     Args:
         min_frequency (int or float):