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authorRalf Gommers <ralf.gommers@gmail.com>2019-02-28 12:24:13 -0800
committerGitHub <noreply@github.com>2019-02-28 12:24:13 -0800
commitc4a840ed97f67cfdc7c5d8a04512cdc86098dff0 (patch)
tree9a13f30deadd78d142fc0153a09a636079a47696 /numpy/doc/glossary.py
parentb9ab1a57b9c7ff9462b8d678bce91274d0ad4d12 (diff)
parent76099ada3cca1d815e1b32f5d0c9786e1c5e0481 (diff)
downloadnumpy-c4a840ed97f67cfdc7c5d8a04512cdc86098dff0.tar.gz
Merge pull request #13002 from mattip/doc-warnings2
DOC: reduce warnings when building, and rephrase slightly
Diffstat (limited to 'numpy/doc/glossary.py')
-rw-r--r--numpy/doc/glossary.py68
1 files changed, 48 insertions, 20 deletions
diff --git a/numpy/doc/glossary.py b/numpy/doc/glossary.py
index a3707340d..7d1c9a1d5 100644
--- a/numpy/doc/glossary.py
+++ b/numpy/doc/glossary.py
@@ -159,7 +159,7 @@ Glossary
field
In a :term:`structured data type`, each sub-type is called a `field`.
- The `field` has a name (a string), a type (any valid :term:`dtype`, and
+ The `field` has a name (a string), a type (any valid dtype, and
an optional `title`. See :ref:`arrays.dtypes`
Fortran order
@@ -209,6 +209,9 @@ Glossary
Key 1: b
Key 2: c
+ itemsize
+ The size of the dtype element in bytes.
+
list
A Python container that can hold any number of objects or items.
The items do not have to be of the same type, and can even be
@@ -345,31 +348,31 @@ Glossary
Painting the city red!
slice
- Used to select only certain elements from a sequence::
+ Used to select only certain elements from a sequence:
- >>> x = range(5)
- >>> x
- [0, 1, 2, 3, 4]
+ >>> x = range(5)
+ >>> x
+ [0, 1, 2, 3, 4]
- >>> x[1:3] # slice from 1 to 3 (excluding 3 itself)
- [1, 2]
+ >>> x[1:3] # slice from 1 to 3 (excluding 3 itself)
+ [1, 2]
- >>> x[1:5:2] # slice from 1 to 5, but skipping every second element
- [1, 3]
+ >>> x[1:5:2] # slice from 1 to 5, but skipping every second element
+ [1, 3]
- >>> x[::-1] # slice a sequence in reverse
- [4, 3, 2, 1, 0]
+ >>> x[::-1] # slice a sequence in reverse
+ [4, 3, 2, 1, 0]
Arrays may have more than one dimension, each which can be sliced
- individually::
+ individually:
- >>> x = np.array([[1, 2], [3, 4]])
- >>> x
- array([[1, 2],
- [3, 4]])
+ >>> x = np.array([[1, 2], [3, 4]])
+ >>> x
+ array([[1, 2],
+ [3, 4]])
- >>> x[:, 1]
- array([2, 4])
+ >>> x[:, 1]
+ array([2, 4])
structure
See :term:`structured data type`
@@ -377,6 +380,20 @@ Glossary
structured data type
A data type composed of other datatypes
+ subarray data type
+ A :term:`structured data type` may contain a :term:`ndarray` with its
+ own dtype and shape:
+
+ >>> dt = np.dtype([('a', np.int32), ('b', np.float32, (3,))])
+ >>> np.zeros(3, dtype=dt)
+ array([(0, [0., 0., 0.]), (0, [0., 0., 0.]), (0, [0., 0., 0.])],
+ dtype=[('a', '<i4'), ('b', '<f4', (3,))])
+
+ title
+ In addition to field names, structured array fields may have an
+ associated :ref:`title <titles>` which is an alias to the name and is
+ commonly used for plotting.
+
tuple
A sequence that may contain a variable number of types of any
kind. A tuple is immutable, i.e., once constructed it cannot be
@@ -413,8 +430,19 @@ Glossary
'alpha'
ufunc
- Universal function. A fast element-wise array operation. Examples include
- ``add``, ``sin`` and ``logical_or``.
+ Universal function. A fast element-wise, :term:`vectorized
+ <vectorization>` array operation. Examples include ``add``, ``sin`` and
+ ``logical_or``.
+
+ vectorization
+ Optimizing a looping block by specialized code. In a traditional sense,
+ vectorization performs the same operation on multiple elements with
+ fixed strides between them via specialized hardware. Compilers know how
+ to take advantage of well-constructed loops to implement such
+ optimizations. NumPy uses :ref:`vectorization <whatis-vectorization>`
+ to mean any optimization via specialized code performing the same
+ operations on multiple elements, typically achieving speedups by
+ avoiding some of the overhead in looking up and converting the elements.
view
An array that does not own its data, but refers to another array's