DEP: Deprecate the pickle aliases

* The np.ma functions are misleading, as they do not actually do anything special for ma.array
* The np.loads functions doesn't even have numpy-specific documentation, and does not behave consistently with `np.load`
* The string overloads of np.ma.load and np.ma.dump do not work well on python 3, as they make assumptions about whether a binary or text pickle file is used (gh-5491)

1 files changed, 14 insertions, 0 deletions

diff --git a/numpy/ma/core.py b/numpy/ma/core.py
index 407869362..04c1c1a6a 100644
--- a/numpy/ma/core.py
+++ b/numpy/ma/core.py
@@ -7859,6 +7859,16 @@ def asanyarray(a, dtype=None):
 ##############################################################################
 #                               Pickling                                     #
 ##############################################################################
+
+def _pickle_warn(method):
+    # NumPy 1.15.0, 2017-12-10
+    warnings.warn(
+        "np.ma.{method} is deprecated, use pickle.{method} instead"
+            .format(method),
+        DeprecationWarning,
+        stacklevel=3)
+
+
 def dump(a, F):
     """
     Pickle a masked array to a file.
@@ -7873,6 +7883,7 @@ def dump(a, F):
         The file to pickle `a` to. If a string, the full path to the file.
 
     """
+    _pickle_warn('dump')
     if not hasattr(F, 'readline'):
         with open(F, 'w') as F:
             pickle.dump(a, F)
@@ -7893,6 +7904,7 @@ def dumps(a):
         returned.
 
     """
+    _pickle_warn('dumps')
     return pickle.dumps(a)
 
 
@@ -7916,6 +7928,7 @@ def load(F):
     the NumPy binary .npy format.
 
     """
+    _pickle_warn('load')
     if not hasattr(F, 'readline'):
         with open(F, 'r') as F:
             pickle.load(F)
@@ -7939,6 +7952,7 @@ def loads(strg):
     dumps : Return a string corresponding to the pickling of a masked array.
 
     """
+    _pickle_warn('loads')
     return pickle.loads(strg)