TST: skip tests when using an old scipy for gaussian_kde #7151
Description
These tests are all marked slow, so not sure if they are being tested on travis. I just enabled them on windows, bunch fail (also some in tests/test_graphics.py), same reason
need to do an additional check not only skip if we don't have scipy, but must have a recent version (not exactly sure when gaussian_kde was added).
using scipy 0.10.1
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ERROR: test_secondary_kde (pandas.tseries.tests.test_plotting.TestTSPlot)
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Traceback (most recent call last):
File "c:\Users\Jeff Reback\Documents\GitHub\pandas\build\lib.win32-2.6\pandas\tseries\tests\test_plotting.py", line 573, in test_secondary_kde
ax = ser.plot(secondary_y=True, kind='density').right_ax
File "c:\Users\Jeff Reback\Documents\GitHub\pandas\build\lib.win32-2.6\pandas\tools\plotting.py", line 2256, in plot_series
plot_obj.generate()
File "c:\Users\Jeff Reback\Documents\GitHub\pandas\build\lib.win32-2.6\pandas\tools\plotting.py", line 902, in generate
self._make_plot()
File "c:\Users\Jeff Reback\Documents\GitHub\pandas\build\lib.win32-2.6\pandas\tools\plotting.py", line 1346, in _make_plot
from scipy.stats import gaussian_kde
File "C:\python26-32\lib\site-packages\scipy\stats\__init__.py", line 322, in <module>
from stats import *
File "C:\python26-32\lib\site-packages\scipy\stats\stats.py", line 198, in <module>
import distributions
File "C:\python26-32\lib\site-packages\scipy\stats\distributions.py", line 14, in <module>
from scipy import optimize
File "C:\python26-32\lib\site-packages\scipy\optimize\__init__.py", line 135, in <module>
from nonlin import *
File "C:\python26-32\lib\site-packages\scipy\optimize\nonlin.py", line 118, in <module>
import scipy.sparse.linalg
File "C:\python26-32\lib\site-packages\scipy\sparse\__init__.py", line 182, in <module>
from csgraph import *
File "C:\python26-32\lib\site-packages\scipy\sparse\csgraph\__init__.py", line 148, in <module>
from ._shortest_path import shortest_path, floyd_warshall, dijkstra,\
ImportError: cannot import name shortest_path