ENH: Implement concatenate dtype and casting keyword arguments

Unfortunately, the casting was not consistent and sometimes used
force casting (axis=None) while normally same kind casting was used.
This thus deprecates the `force_casting` corner case, so that
casting has to be provided in the future.

1 files changed, 12 insertions, 2 deletions

diff --git a/numpy/core/multiarray.py b/numpy/core/multiarray.py
index 10325050d..540c0568f 100644
--- a/numpy/core/multiarray.py
+++ b/numpy/core/multiarray.py
@@ -141,9 +141,9 @@ def empty_like(prototype, dtype=None, order=None, subok=None, shape=None):
 
 
 @array_function_from_c_func_and_dispatcher(_multiarray_umath.concatenate)
-def concatenate(arrays, axis=None, out=None):
+def concatenate(arrays, axis=None, out=None, dtype=None, casting=None):
     """
-    concatenate((a1, a2, ...), axis=0, out=None)
+    concatenate((a1, a2, ...), axis=0, out=None, dtype=None, casting="same_kind")
 
     Join a sequence of arrays along an existing axis.
 
@@ -159,6 +159,16 @@ def concatenate(arrays, axis=None, out=None):
         If provided, the destination to place the result. The shape must be
         correct, matching that of what concatenate would have returned if no
         out argument were specified.
+    dtype : str or dtype
+        If provided, the destination array will have this dtype. Cannot be
+        provided together with `out`.
+
+        ..versionadded:: 1.19.0
+
+    casting : {'no', 'equiv', 'safe', 'same_kind', 'unsafe'}, optional
+        Controls what kind of data casting may occur. Defaults to 'same_kind'.
+
+        ..versionadded:: 1.19.0
 
     Returns
     -------