updated documentation from pydoc website (thanks to everyone who contributed!)

3 files changed, 30 insertions, 14 deletions

diff --git a/numpy/add_newdocs.py b/numpy/add_newdocs.py
index bbb93f6f2..b6c5853e0 100644
--- a/numpy/add_newdocs.py
+++ b/numpy/add_newdocs.py
@@ -3985,6 +3985,12 @@ add_newdoc('numpy.core', 'ufunc',
     """
     Functions that operate element by element on whole arrays.
 
+    To see the documentation for a specific ufunc, use np.info().  For
+    example, np.info(np.sin).  Because ufuncs are written in C
+    (for speed) and linked into Python with NumPy's ufunc facility,
+    Python's help() function finds this page whenever help() is called
+    on a ufunc.
+
     A detailed explanation of ufuncs can be found in the "ufuncs.rst"
     file in the NumPy reference guide.
 
diff --git a/numpy/core/code_generators/ufunc_docstrings.py b/numpy/core/code_generators/ufunc_docstrings.py
index 4adbf2376..c63df7c8f 100644
--- a/numpy/core/code_generators/ufunc_docstrings.py
+++ b/numpy/core/code_generators/ufunc_docstrings.py
@@ -1641,7 +1641,7 @@ add_newdoc('numpy.core.umath', 'left_shift',
     x1 : array_like of integer type
         Input values.
     x2 : array_like of integer type
-        Number of zeros to append to `x1`.
+        Number of zeros to append to `x1`. Has to be non-negative.
 
     Returns
     -------
@@ -1849,6 +1849,16 @@ add_newdoc('numpy.core.umath', 'log2',
     handles the floating-point negative zero as an infinitesimal negative
     number, conforming to the C99 standard.
 
+    Examples
+    --------
+    >>> x = np.array([0, 1, 2, 2**4])
+    >>> np.log2(x)
+    array([-Inf,   0.,   1.,   4.])
+
+    >>> xi = np.array([0+1.j, 1, 2+0.j, 4.j])
+    >>> np.log2(xi)
+    array([ 0.+2.26618007j,  0.+0.j        ,  1.+0.j        ,  2.+2.26618007j])
+
     """)
 
 add_newdoc('numpy.core.umath', 'logaddexp',
diff --git a/numpy/doc/constants.py b/numpy/doc/constants.py
index adb7c7e02..722147dd8 100644
--- a/numpy/doc/constants.py
+++ b/numpy/doc/constants.py
@@ -75,8 +75,8 @@ add_newdoc('numpy', 'NINF',
 
     isnan : Shows which elements are Not a Number
 
-    isfinite : Shows which elements are finite (not one of
-             Not a Number, positive infinity and negative infinity)
+    isfinite : Shows which elements are finite (not one of Not a Number,
+    positive infinity and negative infinity)
 
     Notes
     -----
@@ -214,7 +214,7 @@ add_newdoc('numpy', 'e',
     """
     Euler's constant, base of natural logarithms, Napier's constant.
 
-    `e = 2.71828182845904523536028747135266249775724709369995...`
+    ``e = 2.71828182845904523536028747135266249775724709369995...``
 
     See Also
     --------
@@ -246,8 +246,8 @@ add_newdoc('numpy', 'inf',
 
     isnan : Shows which elements are Not a Number
 
-    isfinite : Shows which elements are finite (not one of
-               Not a Number, positive infinity and negative infinity)
+    isfinite : Shows which elements are finite (not one of Not a Number,
+    positive infinity and negative infinity)
 
     Notes
     -----
@@ -322,20 +322,20 @@ add_newdoc('numpy', 'newaxis',
 
     Examples
     --------
-    >>> np.newaxis is None
+    >>> newaxis is None
     True
     >>> x = np.arange(3)
     >>> x
     array([0, 1, 2])
-    >>> x[:, np.newaxis]
+    >>> x[:, newaxis]
     array([[0],
     [1],
     [2]])
-    >>> x[:, np.newaxis, np.newaxis]
+    >>> x[:, newaxis, newaxis]
     array([[[0]],
     [[1]],
     [[2]]])
-    >>> x[:, np.newaxis] * x
+    >>> x[:, newaxis] * x
     array([[0, 0, 0],
     [0, 1, 2],
     [0, 2, 4]])
@@ -343,20 +343,20 @@ add_newdoc('numpy', 'newaxis',
     Outer product, same as ``outer(x, y)``:
 
     >>> y = np.arange(3, 6)
-    >>> x[:, np.newaxis] * y
+    >>> x[:, newaxis] * y
     array([[ 0,  0,  0],
     [ 3,  4,  5],
     [ 6,  8, 10]])
 
     ``x[newaxis, :]`` is equivalent to ``x[newaxis]`` and ``x[None]``:
 
-    >>> x[np.newaxis, :].shape
+    >>> x[newaxis, :].shape
     (1, 3)
-    >>> x[np.newaxis].shape
+    >>> x[newaxis].shape
     (1, 3)
     >>> x[None].shape
     (1, 3)
-    >>> x[:, np.newaxis].shape
+    >>> x[:, newaxis].shape
     (3, 1)
 
     """)