[NumPy-Tickets] [NumPy] #1899: histogramdd improperly handles empty arrays with known bins
NumPy Trac
numpy-tickets@scipy....
Fri Jul 8 22:39:02 CDT 2011
#1899: histogramdd improperly handles empty arrays with known bins
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Reporter: WeatherGod | Owner: somebody
Type: defect | Status: new
Priority: normal | Milestone: Unscheduled
Component: Other | Version: 1.6.0
Keywords: |
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Subject says it all. In particular, this impacts histogram2d.
histogramdd appears to attempt to handle this case, but doesn't do so
correctly.
{{{
>>> np.histogram2d([], [], bins=4)
(array([ 0., 0.]), array([ 0. , 0.25, 0.5 , 0.75, 1. ]), array([ 0.
, 0.25, 0.5 , 0.75, 1. ]))
}}}
The first element of the return tuple is a 1-D array with two elements.
What is expected is a 2-D 4x4 array. Consider the following with non-empty
inputs:
{{{
>>> np.histogram2d([0.3], [0.7], bins=4)
(array([[ 0., 0., 0., 0.],
[ 0., 0., 0., 0.],
[ 0., 0., 1., 0.],
[ 0., 0., 0., 0.]]), array([-0.2 , 0.05, 0.3 , 0.55, 0.8 ]),
array([ 0.2 , 0.45, 0.7 , 0.95, 1.2 ]))
}}}
For comparison, consider how histogram behaves with empty inputs:
{{{
>>> np.histogram([], bins=4)
(array([0, 0, 0, 0]), array([ 0. , 0.25, 0.5 , 0.75, 1. ]))
}}}
--
Ticket URL: <http://projects.scipy.org/numpy/ticket/1899>
NumPy <http://projects.scipy.org/numpy>
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