Add another constructor

Author: LukeMathWalker

src/doc/ndarray_for_numpy_users/mod.rs

@@ -202,6 +202,7 @@
 //! `np.zeros_like(a, order='C')` | [`Array::zeros(a.raw_dim())`][::zeros()] | create an array of zeros of the shape shape as `a`, with row-major memory layout (unlike NumPy, this infers the element type from context instead of duplicating `a`'s element type)
 //! `np.full((3, 4), 7.)` | [`Array::from_elem((3, 4), 7.)`][::from_elem()] | create a 3×4 array filled with the value `7.`
 //! `np.eye(3)` | [`Array::eye(3)`][::eye()] | create a 3×3 identity matrix (inferring the element type)
+//! `np.diag(np.array([1, 2, 3]))` | [`Array2::from_diag(&arr1(&[1, 2, 3]))`][::from_diag()] | create a 3×3 matrix with `[1, 2, 3]` as diagonal and zeros elsewhere (inferring the element type)
 //! `np.array([1, 2, 3, 4]).reshape((2, 2))` | [`Array::from_shape_vec((2, 2), vec![1, 2, 3, 4])?`][::from_shape_vec()] | create a 2×2 array from the elements in the list/`Vec`
 //! `np.array([1, 2, 3, 4]).reshape((2, 2), order='F')` | [`Array::from_shape_vec((2, 2).f(), vec![1, 2, 3, 4])?`][::from_shape_vec()] | create a 2×2 array from the elements in the list/`Vec` using Fortran (column-major) order
 //! `np.random` | See the [`ndarray-rand`](https://crates.io/crates/ndarray-rand) crate. | create arrays of random numbers
@@ -458,8 +459,7 @@
 //!
 //! </td><td>
 //!
-//! `a.sum() / a.len() as f64`
-//!
+//! [`a.mean().unwrap()`][.mean()]
 //! </td><td>
 //!
 //! calculate the mean of the elements in `f64` array `a`
@@ -490,7 +490,7 @@
 //!
 //! </td><td>
 //!
-//! check if the arrays' elementwise differences are within an absolute tolerance
+//! check if the arrays' elementwise differences are within an absolute tolerance (it requires the `approx` feature-flag)
 //!
 //! </td></tr>
 //!
@@ -514,9 +514,7 @@
 //!
 //! </td><td>
 //!
-//! See other crates, e.g.
-//! [`ndarray-linalg`](https://crates.io/crates/ndarray-linalg) and
-//! [`linxal`](https://crates.io/crates/linxal).
+//! See [`ndarray-linalg`](https://crates.io/crates/ndarray-linalg)
 //!
 //! </td><td>
 //!
@@ -595,6 +593,7 @@
 //! [.fold_axis()]: ../../struct.ArrayBase.html#method.fold_axis
 //! [::from_elem()]: ../../struct.ArrayBase.html#method.from_elem
 //! [::from_iter()]: ../../struct.ArrayBase.html#method.from_iter
+//! [::from_diag()]: ../../struct.ArrayBase.html#method.from_diag
 //! [::from_shape_fn()]: ../../struct.ArrayBase.html#method.from_shape_fn
 //! [::from_shape_vec()]: ../../struct.ArrayBase.html#method.from_shape_vec
 //! [::from_shape_vec_unchecked()]: ../../struct.ArrayBase.html#method.from_shape_vec_unchecked
@@ -618,6 +617,7 @@
 //! [.mapv_inplace()]: ../../struct.ArrayBase.html#method.mapv_inplace
 //! [.mapv_into()]: ../../struct.ArrayBase.html#method.mapv_into
 //! [matrix-* dot]: ../../struct.ArrayBase.html#method.dot-1
+//! [.mean()]: ../../struct.ArrayBase.html#method.mean
 //! [.mean_axis()]: ../../struct.ArrayBase.html#method.mean_axis
 //! [.ndim()]: ../../struct.ArrayBase.html#method.ndim
 //! [NdProducer]: ../../trait.NdProducer.html