area-based calculation?

app.py

@@ -68,7 +68,7 @@ manageable = "https://data.source.coop/cboettig/carbon/cogs/manageable_c_total_2
 
 
 
-m = leafmap.Map(center=[35, -100], zoom=2)
+m = leafmap.Map(center=[35, -100], zoom=3)
 
 ## Map controls sidebar
 with st.sidebar:
@@ -104,14 +104,22 @@ polygon = st_data["last_active_drawing"]
 # Here we actually compute the total carbon in the requested polygon
 if polygon is not None:
     gdf = read_polygon(polygon)
-    x = extract_geom(gdf, cog)
-    value = float(x.sum())
-    if(selection in ["Vulnerable Carbon (2018)",
-                     "Manageable Carbon (2018)",
-                     "Irrecoverable Carbon (2018)"]):
-        value = value * 9 # 300m pixels, each pixel is 9 hectres
-
-    st.metric(label=f"{selection}", value=f"{value:,}  {units}")
+    x = extract_geom(gdf, cog).fillna(0)    
+    count = x.count()
+    area = round(float(area_hectares(gdf)))
+    carbon_total = round(float(x.mean()) * area) # no, mean does not include zeros
+    col1, col2, col3 = st.columns(3)
+    col1.metric(label=f"{selection}", value=f"{carbon_total:,}  {units}")
+    col2.metric(label=f"Area", value=f"{area:,} Hectares")
+    col3.metric(label=f"pixels", value=f"{count:,}")
+
+
+# pixel sums instead of means
+#    value = round(float(x.sum()))
+#    if(selection in ["Vulnerable Carbon (2018)",
+#                     "Manageable Carbon (2018)",
+#                     "Irrecoverable Carbon (2018)"]):
+#        value = value * 9 # 300m pixels, each pixel is 9 hectres
 
 
 st.divider()