adding documentation & removing empty exploratory notebook

src/hrvmeg/preprocess_ecg.py

@@ -6,6 +6,17 @@ import plotter
 
 
 def nk_preproc(ecg_signal, fs):
+    """
+    It takes in an ECG signal and sampling frequency, and returns a dataframe with the raw and cleaned
+    ECG signals
+    
+    Args:
+      ecg_signal: The raw ECG signal
+      fs: sampling frequency
+    
+    Returns:
+      A dataframe with two columns, one for the raw ECG signal and one for the cleaned ECG signal.
+    """
     # Do processing
     ecg_cleaned = nk.ecg_clean(ecg_signal, sampling_rate=fs, method="biosppy")
 
@@ -16,6 +27,19 @@ def nk_preproc(ecg_signal, fs):
 
 
 def preproc_ecg(file_path, fs, downsample_freq, output_folder):
+    """
+    > It takes in the raw ECG data, preprocesses it using the biosppy library, and returns the
+    preprocessed data
+    
+    Args:
+      file_path: the path to the file containing the ECG data
+      fs: sampling frequency of the data
+      downsample_freq: The frequency at which we want to downsample the data.
+      output_folder: The folder where the output files will be saved.
+    
+    Returns:
+      A dictionary of downsampled signals
+    """
     ecg_data = pd.read_csv(file_path)
     signals = nk_preproc(ecg_data.iloc[:, 0], fs)
     downsamp_signals = {}