Merge pull request #3830 from jarondl/recfromcsv

MAINT (API?): organize npyio.recfromcsv defaults

3 files changed, 27 insertions, 10 deletions

diff --git a/doc/release/1.9.0-notes.rst b/doc/release/1.9.0-notes.rst
index b0adec0cf..ea2069c12 100644
--- a/doc/release/1.9.0-notes.rst
+++ b/doc/release/1.9.0-notes.rst
@@ -293,6 +293,12 @@ cases the arrays being iterated are as large as the iterator so that such
 a problem cannot occur.
 
 
+`npyio.recfromcsv` keyword arguments change
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+`npyio.recfromcsv` no longer accepts the undocumented `update` keyword,
+which used to override the `dtype` keyword.
+
+ 
 C-API
 ~~~~~
 
diff --git a/numpy/lib/npyio.py b/numpy/lib/npyio.py
index 4268e6f06..f69ca0c73 100644
--- a/numpy/lib/npyio.py
+++ b/numpy/lib/npyio.py
@@ -1856,7 +1856,7 @@ def recfromtxt(fname, **kwargs):
     array will be determined from the data.
 
     """
-    kwargs.update(dtype=kwargs.get('dtype', None))
+    kwargs.setdefault("dtype", None)
     usemask = kwargs.get('usemask', False)
     output = genfromtxt(fname, **kwargs)
     if usemask:
@@ -1883,17 +1883,20 @@ def recfromcsv(fname, **kwargs):
     --------
     numpy.genfromtxt : generic function to load ASCII data.
 
+    Notes
+    -----
+    By default, `dtype` is None, which means that the data-type of the output
+    array will be determined from the data.
+
     """
-    case_sensitive = kwargs.get('case_sensitive', "lower") or "lower"
-    names = kwargs.get('names', True)
-    if names is None:
-        names = True
-    kwargs.update(dtype=kwargs.get('update', None),
-                  delimiter=kwargs.get('delimiter', ",") or ",",
-                  names=names,
-                  case_sensitive=case_sensitive)
-    usemask = kwargs.get("usemask", False)
+    # Set default kwargs for genfromtxt as relevant to csv import.
+    kwargs.setdefault("case_sensitive", "lower")
+    kwargs.setdefault("names", True)
+    kwargs.setdefault("delimiter", ",")
+    kwargs.setdefault("dtype", None)
     output = genfromtxt(fname, **kwargs)
+
+    usemask = kwargs.get("usemask", False)
     if usemask:
         from numpy.ma.mrecords import MaskedRecords
         output = output.view(MaskedRecords)
diff --git a/numpy/lib/tests/test_io.py b/numpy/lib/tests/test_io.py
index a8b578097..418386e35 100644
--- a/numpy/lib/tests/test_io.py
+++ b/numpy/lib/tests/test_io.py
@@ -1572,6 +1572,14 @@ M   33  21.99
                            dtype=[('a', np.int), ('b', np.int)])
         self.assertTrue(isinstance(test, np.recarray))
         assert_equal(test, control)
+        #
+        data = TextIO('A,B\n0,1\n2,3')
+        dtype = [('a', np.int), ('b', np.float)]
+        test = np.recfromcsv(data, missing_values='N/A', dtype=dtype)
+        control = np.array([(0, 1), (2, 3)],
+                           dtype=dtype)
+        self.assertTrue(isinstance(test, np.recarray))
+        assert_equal(test, control)
 
     def test_gft_using_filename(self):
         # Test that we can load data from a filename as well as a file object