Geometry: ProfileXYZ: Minor optimisation of computation.

src/Model/Geometry/ProfileXYZ.py

@@ -875,7 +875,9 @@ class ProfileXYZ(Profile, SQLSubModel):
         if z in self._get_water_limits_cache:
             return self._get_water_limits_cache[z]
 
-        return self.get_water_limits_compute(z)
+        v = self.get_water_limits_compute(z)
+
+        return v
 
     def get_water_limits_compute(self, z):
         """
@@ -883,54 +885,59 @@ class ProfileXYZ(Profile, SQLSubModel):
         """
         # Get the index of first point with elevation lesser than water
         # elevation (for the right and left river side)
-        i_left = -1
-        i_right = -1
+        i_left = next(
+            filter(
+                lambda i: self.point(i).z <= z,
+                range(self.number_points)
+            ),
+            -1
+        )
 
-        for i in range(self.number_points):
-            if self.point(i).z <= z:
-                i_left = i
-                break
-
-        for i in reversed(range(self.number_points)):
-            if self.point(i).z <= z:
-                i_right = i
-                break
+        i_right = next(
+            filter(
+                lambda i: self.point(i).z <= z,
+                reversed(range(self.number_points))
+            ),
+            -1
+        )
 
         # Interpolate points at river left side
         if (i_left > 0):
-            if abs(self.point(i_left - 1).z - self.point(i_left).z) < 1e-20:
-                pt_left = self.point(i_left)
+            pi = self.point(i_left)
+            pim1 = self.point(i_left - 1)
+
+            if abs(pim1.z - pi.z) < 1e-20:
+                pt_left = pi
             else:
-                fact = (z - self.point(i_left).z) / \
-                    (self.point(i_left - 1).z - self.point(i_left).z)
-                x = self.point(i_left).x + fact * \
-                    (self.point(i_left - 1).x - self.point(i_left).x)
-                y = self.point(i_left).y + fact * \
-                    (self.point(i_left - 1).y - self.point(i_left).y)
+                fact = (z - pi.z) / (pim1.z - pi.z)
+                x = pi.x + fact * (pim1.x - pi.x)
+                y = pi.y + fact * (pim1.y - pi.y)
                 pt_left = PointXYZ(x=x, y=y, z=z, name="wl_left")
         else:
             pt_left = self.point(0)
 
         # Interpolate points at river right side
         if (i_right < self.number_points - 1):
-            if abs(self.point(i_right + 1).z - self.point(i_right).z) < 1e-20:
-                pt_right = self.point(i_right)
+            pi = self.point(i_right)
+            pip1 = self.point(i_right + 1)
+
+            if abs(pip1.z - pi.z) < 1e-20:
+                pt_right = pi
             else:
-                fact = (z - self.point(i_right).z) / \
-                    (self.point(i_right + 1).z - self.point(i_right).z)
-                x = self.point(i_right).x + fact * \
-                    (self.point(i_right + 1).x - self.point(i_right).x)
-                y = self.point(i_right).y + fact * \
-                    (self.point(i_right + 1).y - self.point(i_right).y)
+                fact = (z - pi.z) / (pip1.z - pi.z)
+                x = pi.x + fact * (pip1.x - pi.x)
+                y = pi.y + fact * (pip1.y - pi.y)
                 pt_right = PointXYZ(x=x, y=y, z=z, name="wl_right")
         else:
             pt_right = self.point(self.number_points - 1)
 
+        v = (pt_left, pt_right)
+
         # Put results in cache
-        self._get_water_limits_cache[z] = (pt_left, pt_right)
+        self._get_water_limits_cache[z] = v
 
         # Create a generator to improve results data reading speed
-        yield pt_left, pt_right
+        yield v
 
     @timer
     def compute_tabulation(self):