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authorBernhard Spinnler <Bernhard.Spinnler@gmx.net>2013-10-15 21:21:33 +0200
committerBernhard Spinnler <Bernhard.Spinnler@gmx.net>2013-10-15 21:21:33 +0200
commitf6492d927206cf87006e005f0ab19d2db20bc889 (patch)
tree8aca868ed6abfd27f7d197c250fca3d1732cb1b7 /numpy/core/numeric.py
parent53cafa064698dd877acb82aa1b6319510fe70ef5 (diff)
downloadnumpy-f6492d927206cf87006e005f0ab19d2db20bc889.tar.gz
DOC: replaced typeset formulas by pure ASCII equivalents.
Replaced typeset formulas by pure ASCII equivalents. Should now be easier to read in source files.
Diffstat (limited to 'numpy/core/numeric.py')
-rw-r--r--numpy/core/numeric.py25
1 files changed, 12 insertions, 13 deletions
diff --git a/numpy/core/numeric.py b/numpy/core/numeric.py
index a5f6140f1..fd6295a47 100644
--- a/numpy/core/numeric.py
+++ b/numpy/core/numeric.py
@@ -820,8 +820,13 @@ def correlate(a, v, mode='valid', old_behavior=False):
"""
Cross-correlation of two 1-dimensional sequences.
- This function computes the cross-correlation of two sequences a and v
- as generally defined in signal processing text.
+ This function computes the correlation as generally defined in signal
+ processing texts::
+
+ c_{av}[k] = sum_n a[n+k] * conj(v[n])
+
+ with a and v sequences being zero-padded where necessary and conj being
+ the conjugate.
Parameters
----------
@@ -847,18 +852,12 @@ def correlate(a, v, mode='valid', old_behavior=False):
Notes
-----
- The discrete cross-correlation of two sequences a and v is defined as
-
- .. math:: c_{av}[k] = \\sum_{n = -\\infty}^{\\infty} a[n+k] v^{*}[n]
-
- where :math:`v^{*}[n]` is the complex conjugate of :math:`v[n]`.
-
- Note that sometimes correlation may be defined differently.
- Another common definition is
+ The definition of correlation above is not unique and sometimes correlation
+ may be defined differently. Another common definition is::
- .. math:: c'_{av}[k] = \\sum_{n = -\\infty}^{\\infty} a[n] v^{*}[n+k]
+ c'_{av}[k] = sum_n a[n] conj(v[n+k])
- which is related to :math:`c_{av}[k]` by :math:`c'_{av}[k] = c_{av}[-k]`.
+ which is related to ``c_{av}[k]`` by ``c'_{av}[k] = c_{av}[-k]``.
Examples
--------
@@ -876,7 +875,7 @@ def correlate(a, v, mode='valid', old_behavior=False):
Note that you get the time reversed, complex conjugated result
when the two input sequences change places, i.e.,
- :math:`c_{va}[k] = c^{*}_{av}[-k]`:
+ ``c_{va}[k] = c^{*}_{av}[-k]``:
>>> np.correlate([0, 1, 0.5j], [1+1j, 2, 3-1j], 'full')
array([ 0.0+0.j , 3.0+1.j , 1.5+1.5j, 1.0+0.j , 0.5+0.5j])