fix smoothing last 7 axis with incomplete data

aqi_monitor_py/sensor/sensor_sds011.py

@@ -32,7 +32,9 @@ class SDS:
     def startup(self):
         """activate and set mode"""
         self.pm.active = 1
-        sleep(0.5)
+        while self.pm.active.get("value") != 1:
+            sleep(0.5)
+
         self.pm.mode = simple_sds011.MODE_PASSIVE
         print("warm up sensor")
         sleep(20)

web/src/graph_monthly.py

@@ -197,6 +197,7 @@ class MonthGenerator():
         plt.tight_layout()
         plt.savefig(file_name, dpi=300)
         plt.figure()
+        plt.close()
 
     @staticmethod
     def get_aqi(val):

web/src/graph_nightly.py

@@ -160,7 +160,11 @@ class LastSevenDays:
         mean['avg'][0] = (mean['avg'].iloc[6] + mean['aqi'][0]) / 2
         mean['avg'][-1] = (mean['avg'].iloc[-6] + mean['aqi'][-1]) / 2
         # smooth
-        mean['avg'].interpolate(method='polynomial', order=3, inplace=True)
+        try:
+            mean['avg'].interpolate(method='polynomial', order=3, inplace=True)
+        except ValueError:
+            mean['avg'].interpolate(method='polynomial', order=1, inplace=True)
+
         mean.reset_index(level=0, inplace=True)
         mean['timestamp'] = mean['timestamp'].dt.strftime('%Y-%m-%d %H:%M')
         mean['aqi'] = mean['aqi'].round()