optimization of function: speedup 2.86

scenariosAleatoires/resilience_list.py

@@ -11,6 +11,13 @@ class Resilience:
 		:param grille: Grid divising the PAT in squares
 		'''
 		self.grid = gpd.GeoDataFrame.from_file(grille)
+		intersection = gpd.sjoin(
+			self.grid[['id','geometry']],
+		 	patches[['geometry','SURF_PARC']],
+			how='inner', op='intersects')
+		self.grouped_by_cell = intersection.groupby('id')
+		self.size = len(self.grouped_by_cell)
+		self.surfaces = intersection[['id','SURF_PARC']].groupby('id').sum()
 
 	# The parameters are : the grid layer, a list corresponding to a scenario and a boolean value True or False signifying if we want to see the printing lines or not
 	def compute_indicator(self, patches, affichage=False):
@@ -28,21 +35,21 @@ class Resilience:
 		:param patches: The scenario to analyse as a list
 		:param affichage: True if we want the display in the console, False is the other case
 		'''
-		intersection = gpd.sjoin(
-			self.grid[['id','geometry']],
-		 	patches[['geometry','cultgeopat','SURF_PARC']],
-			how='inner', op='intersects')
 		resilience = 0
-		grouped_by_cell = intersection.groupby('id')
-		for cell,group_by_cell in grouped_by_cell:
-			surf_tot = group_by_cell['SURF_PARC'].sum()
-			prop_cult = group_by_cell.groupby('cultgeopat')['SURF_PARC'].sum() / surf_tot
+		for cell,group_by_cell in self.grouped_by_cell:
+			surf_tot = self.surfaces.loc[cell].values[0]
+			intersection = patches[['ID_PARCEL','cultgeopat','SURF_PARC']].loc[group_by_cell['index_right']]
+			prop_cult = intersection.groupby('cultgeopat')['SURF_PARC'].sum() / surf_tot
 			res_cell = - (prop_cult * prop_cult.apply(math.log2)).sum()
 			resilience += res_cell
-		return resilience / len(grouped_by_cell)
+		return resilience / self.size
 
 if __name__ == '__main__':
 	import geopandas as gpd
 	patches = gpd.GeoDataFrame.from_file("../output/PAT_patches/PAT_patches.shp", encoding='utf-8')
+	import time
 	res = Resilience("Parcelle_PAT/Grille_resilience.shp")
+	start = time.time()
 	print(res.compute_indicator(patches))
+	elapsed = time.time()-start
+	print(elapsed)