add derivative

labsw/__init__.py

@@ -1 +1 @@
-__version__ = '0.1.5.3'
+__version__ = '0.1.5.4'

labsw/io.py

@@ -2,6 +2,8 @@ import pandas as pd
 import numpy as np
 import yaml
 
+from scipy.signal import savgol_filter
+
 
 def load_data_RH_logger(filepath, every=1):
     """
@@ -21,6 +23,10 @@ def load_data_RH_logger(filepath, every=1):
     # Crop data
     df = df.reset_index()
     del df['index']
+
+    # Derivative
+    df['dmdt'] = savgol_filter(df['weight'], window_length=10000, polyorder=1, deriv=1)
+
     return df.iloc[::every]