numpy · charris · Jan 20, 2018 · Jan 15, 2018 · Jan 16, 2018 · Jan 16, 2018
diff --git a/doc/release/1.15.0-notes.rst b/doc/release/1.15.0-notes.rst
@@ -15,6 +15,13 @@ New functions
 * `np.ma.stack`, the `np.stack` array-joining function generalized to masked
   arrays.
 
+* `np.printoptions`, the context manager which sets print options temporarily
+  for the scope of the ``with`` block::
+
+    >>> with np.printoptions(precision=2):
+    ...     print(np.array([2.0])) / 3
+    [0.67] 
+
 
 Deprecations
 ============

diff --git a/numpy/core/arrayprint.py b/numpy/core/arrayprint.py
@@ -6,8 +6,8 @@
 from __future__ import division, absolute_import, print_function
 
 __all__ = ["array2string", "array_str", "array_repr", "set_string_function",
-           "set_printoptions", "get_printoptions", "format_float_positional",
-           "format_float_scientific"]
+           "set_printoptions", "get_printoptions", "printoptions",
+           "format_float_positional", "format_float_scientific"]
 __docformat__ = 'restructuredtext'
 
 #
@@ -49,7 +49,7 @@
 from .numerictypes import (longlong, intc, int_, float_, complex_, bool_,
                            flexible)
 import warnings
-
+import contextlib
 
 _format_options = {
     'edgeitems': 3,  # repr N leading and trailing items of each dimension
@@ -273,6 +273,39 @@ def get_printoptions():
     return _format_options.copy()
 
 
+@contextlib.contextmanager
+def printoptions(*args, **kwargs):
+    """Context manager for setting print options.
+
+    Set print options for the scope of the `with` block, and restore the old
+    options at the end. See `set_printoptions` for the full description of
+    available options.
+
+    Examples
+    --------
+
+    >>> with np.printoptions(precision=2):
+    ...     print(np.array([2.0])) / 3
+    [0.67]
+
+    The `as`-clause of the `with`-statement gives the current print options:
+
+    >>> with np.printoptions(precision=2) as opts:
+    ...      assert_equal(opts, np.get_printoptions())
+
+    See Also
+    --------
+    set_printoptions, get_printoptions
+
+    """
+    opts = np.get_printoptions()
+    try:
+        np.set_printoptions(*args, **kwargs)
+        yield np.get_printoptions()
+    finally:
+        np.set_printoptions(**opts)
+
+
 def _leading_trailing(a, edgeitems, index=()):
     """
     Keep only the N-D corners (leading and trailing edges) of an array.

diff --git a/numpy/core/tests/test_arrayprint.py b/numpy/core/tests/test_arrayprint.py
@@ -721,5 +721,37 @@ def test_unicode_object_array():
     assert_equal(repr(x), expected)
 
 
+class TestContextManager(object):
+    def test_ctx_mgr(self):
+        # test that context manager actuall works
+        with np.printoptions(precision=2):
+            s = str(np.array([2.0]) / 3)
+        assert_equal(s, '[0.67]')
+
+    def test_ctx_mgr_restores(self):
+        # test that print options are actually restrored
+        opts = np.get_printoptions()
+        with np.printoptions(precision=opts['precision'] - 1,
+                             linewidth=opts['linewidth'] - 4):
+            pass
+        assert_equal(np.get_printoptions(), opts)
+
+    def test_ctx_mgr_exceptions(self):
+        # test that print options are restored even if an exeption is raised
+        opts = np.get_printoptions()
+        try:
+            with np.printoptions(precision=2, linewidth=11):
+                raise ValueError
+        except ValueError:
+            pass
+        assert_equal(np.get_printoptions(), opts)
+
+    def test_ctx_mgr_as_smth(self):
+        opts = {"precision": 2}
+        with np.printoptions(**opts) as ctx:
+            saved_opts = ctx.copy()
+        assert_equal({k: saved_opts[k] for k in opts}, opts)
+
+
 if __name__ == "__main__":
     run_module_suite()