/rpy/robjects/tests/testPandasConversions.py

import unittest
import rpy2.robjects as robjects

from collections import OrderedDict
from datetime import datetime

# XXX - this is inconsistent with how test_ggplot2 is handled
# See rpy2/robjects/lib/tests/__init__.py for the details
try:
    import pandas
    import numpy
    has_pandas = True
    import rpy2.robjects.pandas2ri as rpyp
except:
    has_pandas = False


class MissingPandasDummyTestCase(unittest.TestCase):
    def testMissingPandas(self):
        self.assertTrue(False) # pandas is missing. No tests.

class PandasConversionsTestCase(unittest.TestCase):

    def setUp(self):
        rpyp.activate()

    def tearDown(self):
        robjects.conversion.py2ri = robjects.default_py2ri
        robjects.conversion.ri2py = robjects.default_ri2py

    def testDataFrame(self):
        l = (('b', numpy.array([True, False, True], dtype=numpy.bool_)),
             ('i', numpy.array([1, 2, 3], dtype="i")),
             ('f', numpy.array([1, 2, 3], dtype="f")),
             ('s', numpy.array(["a", "b", "c"], dtype="S")),
             ('u', numpy.array([u"a", u"b", u"c"], dtype="U")),
             ('dates', [datetime(2012, 5, 2), 
                        datetime(2012, 6, 3), 
                        datetime(2012, 7, 1)]))
        od = OrderedDict(l)
        pd_df = pandas.core.frame.DataFrame(od)
        rp_df = robjects.conversion.py2ri(pd_df)
        self.assertEqual(pd_df.shape[0], rp_df.nrow)
        self.assertEqual(pd_df.shape[1], rp_df.ncol)

    def testDataFrame_PR130(self):
        # PR #130
        a = pandas.core.frame.DataFrame(dict(dates=['05-01-2001', '04-01-2013'], 
                                             not_necessary=[1, 2]))
        a.dates = pandas.to_datetime(a.dates)
        r_dataf = rpyp.pandas2ri(a)
        self.assertIsInstance(r_dataf, robjects.DataFrame)

    def testSeries(self):
        Series = pandas.core.series.Series
        s = Series(numpy.random.randn(5), index=['a', 'b', 'c', 'd', 'e'])
        rp_s = robjects.conversion.py2ri(s)
        self.assertIsInstance(rp_s, robjects.Array)

    def testRepr(self):
        # this should go to testVector, with other tests for repr()
        l = (('b', numpy.array([True, False, True], dtype=numpy.bool_)),
             ('i', numpy.array([1, 2, 3], dtype="i")),
             ('f', numpy.array([1, 2, 3], dtype="f")),
             ('s', numpy.array(["a", "b", "c"], dtype="S")),
             ('u', numpy.array([u"a", u"b", u"c"], dtype="U")))
        od = OrderedDict(l)
        pd_df = pandas.core.frame.DataFrame(od)
        rp_df = robjects.conversion.py2ri(pd_df)
        s = repr(rp_df) # used to fail with a TypeError
        s = s.split('\n')
        self.assertEqual('[Array, Array, Array, FactorV..., FactorV...]', s[1].strip())

    def testPandas2ri(self):
        # XXX - not a full test, just tests that the function returns the right
        # class. This is currently also the case with some of the tests above
        # (e.g., testSeries)
        rdataf = robjects.r('data.frame(a=1:2, b=c("a", "b"))')
        # Note - I'm following the convention above, but this conflates
        # .activate() with testing the function, so it's not as "unit" as it
        # could be.
        pandas_df = robjects.conversion.ri2py(rdataf)
        self.assertIsInstance(pandas_df, pandas.DataFrame)

def suite():
    if has_pandas:
        return unittest.TestLoader().loadTestsFromTestCase(PandasConversionsTestCase)
    else:
        return unittest.TestLoader().loadTestsFromTestCase(MissingPandasDummyTestCase)

if __name__ == '__main__':
    unittest.main(defaultTest='suite')