Add outer product specification

data-apis · rgommers · Sep 8, 2020 · Aug 24, 2020 · Aug 24, 2020 · Aug 24, 2020
commit 20164af9a4d8aef55e575dd834fd1a2990c8fc84
diff --git a/spec/API_specification/linear_algebra_functions.md b/spec/API_specification/linear_algebra_functions.md
@@ -160,3 +160,22 @@ Computes the matrix or vector norm of `a`.
 
     -   an array containing the norms. Must have the same data type as `a`. If `axis` is a scalar value (`int` or `float`), the output array has a rank which is one less than the rank of `a`. If `axis` is a 2-tuple, the output array has a rank which is two less than the rank of `a`.
 
+### <a name="outer" href="#outer">#</a> outer(a, b, /)
+
+Computes the outer product of two vectors `a` and `b`.
+
+#### Parameters
+
+-   **a**: _&lt;array&gt;_
+
+    -   first one-dimensional input array of size `N`.
+
+-   **b**: _&lt;array&gt;_
+
+    -   second one-dimensional input array of size `M`.
+
+#### Returns
+
+-   **out**: _&lt;array&gt;_
+
+    -   a two-dimensional array containing the outer product and whose shape is `NxM`.
diff --git a/spec/purpose_and_scope.md b/spec/purpose_and_scope.md
@@ -66,6 +66,10 @@ two arrays whose dimensions are compatible (i.e., where the size of each dimensi
 
 an operation performed element-by-element, in which individual array elements are considered in isolation and independently of other elements within the same array.
 
+### matrix
+
+a two-dimensional array.
+
 ### rank
 
 number of array dimensions (not to be confused with the number of linearly independent columns of a matrix).
@@ -78,6 +82,10 @@ a tuple of `N` non-negative integers that specify the sizes of each dimension an
 
 a dimension whose size is one.
 
+### vector
+
+a one-dimensional array.
+
 * * *
 
 ## Normative References