Update gauss-quad to 0.2 (#261)

* Update `gauss-quad` to version 0.2.

* `cargo fmt` only my changes.

feos-dft/Cargo.toml

@@ -29,7 +29,7 @@ rustdct = "0.7"
 rustfft = "6.0"
 num-traits = "0.2"
 libm = "0.2"
-gauss-quad = { version = "0.1", optional = true }
+gauss-quad = { version = "0.2", optional = true }
 petgraph = "0.6"
 typenum = "1.16"
 numpy = { version = "0.22", optional = true }

feos-dft/src/adsorption/fea_potential.rs

@@ -54,8 +54,12 @@ pub fn calculate_fea_potential(
             (nodes, weights)
         }
         Geometry::Spherical | Geometry::Cylindrical => {
-            let nodes = PI + Array1::from_vec(GaussLegendre::nodes_and_weights(n_grid[0]).0) * PI;
-            let weights = Array1::from_vec(GaussLegendre::nodes_and_weights(n_grid[0]).1) * PI;
+            let (unscaled_nodes, unscaled_weights) =
+                GaussLegendre::new(n_grid[0]).unwrap().into_iter().unzip();
+
+            let nodes = PI + Array1::from_vec(unscaled_nodes) * PI;
+            let weights = Array1::from_vec(unscaled_weights) * PI;
+
             (nodes, weights)
         }
     };
@@ -75,11 +79,13 @@ pub fn calculate_fea_potential(
             (nodes, weights)
         }
         Geometry::Spherical => {
-            let nodes = PI / 2.0
-                + Array1::from_vec(GaussLegendre::nodes_and_weights(n_grid[1]).0) * PI / 2.0;
-            let weights = Array1::from_vec(GaussLegendre::nodes_and_weights(n_grid[1]).1) * PI
-                / 2.0
+            let (unscaled_nodes, unscaled_weights) =
+                GaussLegendre::new(n_grid[1]).unwrap().into_iter().unzip();
+
+            let nodes = PI / 2.0 + Array1::from_vec(unscaled_nodes) * PI / 2.0;
+            let weights = Array1::from_vec(unscaled_weights) * PI / 2.0
                 * Array1::from_shape_fn(n_grid[1], |i| nodes[i].sin());
+
             (nodes, weights)
         }
     };