Eliminate Warning. Set smoothed value to zero for std. dev. of zero

Author: SabineHaas

windpowerlib/power_curves.py

@@ -142,17 +142,21 @@ def smooth_power_curve(power_curve_wind_speeds, power_curve_values,
             if standard_deviation_method is 'Staffell_Pfenninger'
             else power_curve_wind_speed * normalized_standard_deviation)
         # Get the smoothed value of the power output
-        smoothed_value = sum(
-            block_width * np.interp(wind_speed, power_curve_wind_speeds,
-                                    power_curve_values, left=0, right=0) *
-            tools.gauss_distribution(
-                power_curve_wind_speed - wind_speed,
-                standard_deviation, mean_gauss)
-            for wind_speed in wind_speeds_block)
+        if standard_deviation == 0.0:
+            # The gaussian distribution is not defined for a standard deviation
+            # of zero. Smoothed power curve value is set to zero.
+            smoothed_value = 0.0
+        else:
+            smoothed_value = sum(
+                block_width * np.interp(wind_speed, power_curve_wind_speeds,
+                                        power_curve_values, left=0, right=0) *
+                tools.gauss_distribution(
+                    power_curve_wind_speed - wind_speed,
+                    standard_deviation, mean_gauss)
+                for wind_speed in wind_speeds_block)
         # Add value to list - add zero if `smoothed_value` is nan as Gauss
         # distribution for a standard deviation of zero.
-        smoothed_power_curve_values.append(0 if np.isnan(smoothed_value)
-                                           else smoothed_value)
+        smoothed_power_curve_values.append(smoothed_value)
     # Create smoothed power curve data frame
     smoothed_power_curve_df = pd.DataFrame(
         data=[list(power_curve_wind_speeds.values),