BUG: PeriodIndex.order doesnt preserve freq

doc/source/whatsnew/v0.17.0.txt

@@ -612,5 +612,8 @@ Bug Fixes
 - Bug in ``io.common.get_filepath_or_buffer`` which caused reading of valid S3 files to fail if the bucket also contained keys for which the user does not have read permission (:issue:`10604`)
 - Bug in vectorised setting of timestamp columns with python ``datetime.date`` and numpy ``datetime64`` (:issue:`10408`, :issue:`10412`)
 
+
 - Bug in ``pd.DataFrame`` when constructing an empty DataFrame with a string dtype (:issue:`9428`)
 - Bug in ``pd.unique`` for arrays with the ``datetime64`` or ``timedelta64`` dtype that meant an array with object dtype was returned instead the original dtype (:issue: `9431`)
+- Bug in ``DatetimeIndex.take`` and ``TimedeltaIndex.take`` may not raise ``IndexError`` against invalid index (:issue:`10295`)
+- Bug in ``PeriodIndex.order`` reset freq (:issue:`10295`)

pandas/core/index.py

@@ -2486,7 +2486,7 @@ def get_slice_bound(self, label, side, kind):
             if is_bool_dtype(slc):
                 slc = lib.maybe_booleans_to_slice(slc.view('u1'))
             else:
-                slc = lib.maybe_indices_to_slice(slc.astype('i8'))
+                slc = lib.maybe_indices_to_slice(slc.astype('i8'), len(self))
             if isinstance(slc, np.ndarray):
                 raise KeyError(
                     "Cannot get %s slice bound for non-unique label:"
@@ -5108,7 +5108,7 @@ def _maybe_to_slice(loc):
             if not isinstance(loc, np.ndarray) or loc.dtype != 'int64':
                 return loc
 
-            loc = lib.maybe_indices_to_slice(loc)
+            loc = lib.maybe_indices_to_slice(loc, len(self))
             if isinstance(loc, slice):
                 return loc
 

pandas/lib.pyx

@@ -633,17 +633,42 @@ def convert_timestamps(ndarray values):
 
     return out
 
-def maybe_indices_to_slice(ndarray[int64_t] indices):
+
+def maybe_indices_to_slice(ndarray[int64_t] indices, int max_len):
     cdef:
         Py_ssize_t i, n = len(indices)
+        int k, vstart, vlast, v
+
+    if n == 0:
+        return slice(0, 0)
 
-    if not n or indices[0] < 0:
+    vstart = indices[0]
+    if vstart < 0 or max_len <= vstart:
         return indices
 
-    for i in range(1, n):
-        if indices[i] - indices[i - 1] != 1:
-            return indices
-    return slice(indices[0], indices[n - 1] + 1)
+    if n == 1:
+        return slice(vstart, vstart + 1)
+
+    vlast = indices[n - 1]
+    if vlast < 0 or max_len <= vlast:
+        return indices
+
+    k = indices[1] - indices[0]
+    if k == 0:
+        return indices
+    else:
+        for i in range(2, n):
+            v = indices[i]
+            if v - indices[i - 1] != k:
+                return indices
+
+        if k > 0:
+            return slice(vstart, vlast + 1, k)
+        else:
+            if vlast == 0:
+                return slice(vstart, None, k)
+            else:
+                return slice(vstart, vlast - 1, k)
 
 
 def maybe_booleans_to_slice(ndarray[uint8_t] mask):

pandas/tests/test_index.py

@@ -2266,6 +2266,16 @@ def test_get_loc_na(self):
 
         idx = Float64Index([np.nan, 1, np.nan])
         self.assertEqual(idx.get_loc(1), 1)
+
+        # representable by slice [0:2:2]
+        # self.assertRaises(KeyError, idx.slice_locs, np.nan)
+        sliced = idx.slice_locs(np.nan)
+        self.assertTrue(isinstance(sliced, tuple))
+        self.assertEqual(sliced, (0, 3))
+
+        # not representable by slice
+        idx = Float64Index([np.nan, 1, np.nan, np.nan])
+        self.assertEqual(idx.get_loc(1), 1)
         self.assertRaises(KeyError, idx.slice_locs, np.nan)
 
     def test_contains_nans(self):

pandas/tests/test_lib.py

@@ -4,7 +4,7 @@
 import numpy as np
 
 import pandas as pd
-from pandas.lib import isscalar, item_from_zerodim, max_len_string_array
+import pandas.lib as lib
 import pandas.util.testing as tm
 from pandas.compat import u, PY2
 
@@ -14,19 +14,19 @@ class TestMisc(tm.TestCase):
     def test_max_len_string_array(self):
 
         arr = a = np.array(['foo', 'b', np.nan], dtype='object')
-        self.assertTrue(max_len_string_array(arr), 3)
+        self.assertTrue(lib.max_len_string_array(arr), 3)
 
         # unicode
         arr = a.astype('U').astype(object)
-        self.assertTrue(max_len_string_array(arr), 3)
+        self.assertTrue(lib.max_len_string_array(arr), 3)
 
         # bytes for python3
         arr = a.astype('S').astype(object)
-        self.assertTrue(max_len_string_array(arr), 3)
+        self.assertTrue(lib.max_len_string_array(arr), 3)
 
         # raises
         tm.assertRaises(TypeError,
-                        lambda: max_len_string_array(arr.astype('U')))
+                        lambda: lib.max_len_string_array(arr.astype('U')))
 
     def test_infer_dtype_bytes(self):
         compare = 'string' if PY2 else 'bytes'
@@ -39,68 +39,197 @@ def test_infer_dtype_bytes(self):
         arr = arr.astype(object)
         self.assertEqual(pd.lib.infer_dtype(arr), compare)
 
-
-class TestIsscalar(tm.TestCase):
+    def test_maybe_indices_to_slice_left_edge(self):
+        target = np.arange(100)
+
+        # slice
+        indices = np.array([], dtype=np.int64)
+        maybe_slice = lib.maybe_indices_to_slice(indices, len(target))
+        self.assertTrue(isinstance(maybe_slice, slice))
+        self.assert_numpy_array_equal(target[indices], target[maybe_slice])
+
+        for end in [1, 2, 5, 20, 99]:
+            for step in [1, 2, 4]:
+                indices = np.arange(0, end, step, dtype=np.int64)
+                maybe_slice = lib.maybe_indices_to_slice(indices, len(target))
+                self.assertTrue(isinstance(maybe_slice, slice))
+                self.assert_numpy_array_equal(target[indices], target[maybe_slice])
+
+                # reverse
+                indices = indices[::-1]
+                maybe_slice = lib.maybe_indices_to_slice(indices, len(target))
+                self.assertTrue(isinstance(maybe_slice, slice))
+                self.assert_numpy_array_equal(target[indices], target[maybe_slice])
+
+        # not slice
+        for case in [[2, 1, 2, 0], [2, 2, 1, 0], [0, 1, 2, 1], [-2, 0, 2], [2, 0, -2]]:
+            indices = np.array(case, dtype=np.int64)
+            maybe_slice = lib.maybe_indices_to_slice(indices, len(target))
+            self.assertFalse(isinstance(maybe_slice, slice))
+            self.assert_numpy_array_equal(maybe_slice, indices)
+            self.assert_numpy_array_equal(target[indices], target[maybe_slice])
+
+    def test_maybe_indices_to_slice_right_edge(self):
+        target = np.arange(100)
+
+        # slice
+        for start in [0, 2, 5, 20, 97, 98]:
+            for step in [1, 2, 4]:
+                indices = np.arange(start, 99, step, dtype=np.int64)
+                maybe_slice = lib.maybe_indices_to_slice(indices, len(target))
+                self.assertTrue(isinstance(maybe_slice, slice))
+                self.assert_numpy_array_equal(target[indices], target[maybe_slice])
+
+                # reverse
+                indices = indices[::-1]
+                maybe_slice = lib.maybe_indices_to_slice(indices, len(target))
+                self.assertTrue(isinstance(maybe_slice, slice))
+                self.assert_numpy_array_equal(target[indices], target[maybe_slice])
+
+        # not slice
+        indices = np.array([97, 98, 99, 100], dtype=np.int64)
+        maybe_slice = lib.maybe_indices_to_slice(indices, len(target))
+        self.assertFalse(isinstance(maybe_slice, slice))
+        self.assert_numpy_array_equal(maybe_slice, indices)
+        with self.assertRaises(IndexError):
+            target[indices]
+        with self.assertRaises(IndexError):
+            target[maybe_slice]
+
+        indices = np.array([100, 99, 98, 97], dtype=np.int64)
+        maybe_slice = lib.maybe_indices_to_slice(indices, len(target))
+        self.assertFalse(isinstance(maybe_slice, slice))
+        self.assert_numpy_array_equal(maybe_slice, indices)
+        with self.assertRaises(IndexError):
+            target[indices]
+        with self.assertRaises(IndexError):
+            target[maybe_slice]
+
+        for case in [[99, 97, 99, 96], [99, 99, 98, 97], [98, 98, 97, 96]]:
+            indices = np.array(case, dtype=np.int64)
+            maybe_slice = lib.maybe_indices_to_slice(indices, len(target))
+            self.assertFalse(isinstance(maybe_slice, slice))
+            self.assert_numpy_array_equal(maybe_slice, indices)
+            self.assert_numpy_array_equal(target[indices], target[maybe_slice])
+
+    def test_maybe_indices_to_slice_both_edges(self):
+        target = np.arange(10)
+
+        # slice
+        for step in [1, 2, 4, 5, 8, 9]:
+            indices = np.arange(0, 9, step, dtype=np.int64)
+            maybe_slice = lib.maybe_indices_to_slice(indices, len(target))
+            self.assertTrue(isinstance(maybe_slice, slice))
+            self.assert_numpy_array_equal(target[indices], target[maybe_slice])
+
+            # reverse
+            indices = indices[::-1]
+            maybe_slice = lib.maybe_indices_to_slice(indices, len(target))
+            self.assertTrue(isinstance(maybe_slice, slice))
+            self.assert_numpy_array_equal(target[indices], target[maybe_slice])
+
+        # not slice
+        for case in [[4, 2, 0, -2], [2, 2, 1, 0], [0, 1, 2, 1]]:
+            indices = np.array(case, dtype=np.int64)
+            maybe_slice = lib.maybe_indices_to_slice(indices, len(target))
+            self.assertFalse(isinstance(maybe_slice, slice))
+            self.assert_numpy_array_equal(maybe_slice, indices)
+            self.assert_numpy_array_equal(target[indices], target[maybe_slice])
+
+    def test_maybe_indices_to_slice_middle(self):
+        target = np.arange(100)
+
+        # slice
+        for start, end in [(2, 10), (5, 25), (65, 97)]:
+            for step in [1, 2, 4, 20]:
+                indices = np.arange(start, end, step, dtype=np.int64)
+                maybe_slice = lib.maybe_indices_to_slice(indices, len(target))
+                self.assertTrue(isinstance(maybe_slice, slice))
+                self.assert_numpy_array_equal(target[indices], target[maybe_slice])
+
+                # reverse
+                indices = indices[::-1]
+                maybe_slice = lib.maybe_indices_to_slice(indices, len(target))
+                self.assertTrue(isinstance(maybe_slice, slice))
+                self.assert_numpy_array_equal(target[indices], target[maybe_slice])
+
+        # not slice
+        for case in [[14, 12, 10, 12], [12, 12, 11, 10], [10, 11, 12, 11]]:
+            indices = np.array(case, dtype=np.int64)
+            maybe_slice = lib.maybe_indices_to_slice(indices, len(target))
+            self.assertFalse(isinstance(maybe_slice, slice))
+            self.assert_numpy_array_equal(maybe_slice, indices)
+            self.assert_numpy_array_equal(target[indices], target[maybe_slice])
+
+
+class Testisscalar(tm.TestCase):
 
     def test_isscalar_builtin_scalars(self):
-        self.assertTrue(isscalar(None))
-        self.assertTrue(isscalar(True))
-        self.assertTrue(isscalar(False))
-        self.assertTrue(isscalar(0.))
-        self.assertTrue(isscalar(np.nan))
-        self.assertTrue(isscalar('foobar'))
-        self.assertTrue(isscalar(b'foobar'))
-        self.assertTrue(isscalar(u('efoobar')))
-        self.assertTrue(isscalar(datetime(2014, 1, 1)))
-        self.assertTrue(isscalar(date(2014, 1, 1)))
-        self.assertTrue(isscalar(time(12, 0)))
-        self.assertTrue(isscalar(timedelta(hours=1)))
-        self.assertTrue(isscalar(pd.NaT))
+        self.assertTrue(lib.isscalar(None))
+        self.assertTrue(lib.isscalar(True))
+        self.assertTrue(lib.isscalar(False))
+        self.assertTrue(lib.isscalar(0.))
+        self.assertTrue(lib.isscalar(np.nan))
+        self.assertTrue(lib.isscalar('foobar'))
+        self.assertTrue(lib.isscalar(b'foobar'))
+        self.assertTrue(lib.isscalar(u('efoobar')))
+        self.assertTrue(lib.isscalar(datetime(2014, 1, 1)))
+        self.assertTrue(lib.isscalar(date(2014, 1, 1)))
+        self.assertTrue(lib.isscalar(time(12, 0)))
+        self.assertTrue(lib.isscalar(timedelta(hours=1)))
+        self.assertTrue(lib.isscalar(pd.NaT))
 
     def test_isscalar_builtin_nonscalars(self):
-        self.assertFalse(isscalar({}))
-        self.assertFalse(isscalar([]))
-        self.assertFalse(isscalar([1]))
-        self.assertFalse(isscalar(()))
-        self.assertFalse(isscalar((1,)))
-        self.assertFalse(isscalar(slice(None)))
-        self.assertFalse(isscalar(Ellipsis))
+        self.assertFalse(lib.isscalar({}))
+        self.assertFalse(lib.isscalar([]))
+        self.assertFalse(lib.isscalar([1]))
+        self.assertFalse(lib.isscalar(()))
+        self.assertFalse(lib.isscalar((1,)))
+        self.assertFalse(lib.isscalar(slice(None)))
+        self.assertFalse(lib.isscalar(Ellipsis))
 
     def test_isscalar_numpy_array_scalars(self):
-        self.assertTrue(isscalar(np.int64(1)))
-        self.assertTrue(isscalar(np.float64(1.)))
-        self.assertTrue(isscalar(np.int32(1)))
-        self.assertTrue(isscalar(np.object_('foobar')))
-        self.assertTrue(isscalar(np.str_('foobar')))
-        self.assertTrue(isscalar(np.unicode_(u('foobar'))))
-        self.assertTrue(isscalar(np.bytes_(b'foobar')))
-        self.assertTrue(isscalar(np.datetime64('2014-01-01')))
-        self.assertTrue(isscalar(np.timedelta64(1, 'h')))
+        self.assertTrue(lib.isscalar(np.int64(1)))
+        self.assertTrue(lib.isscalar(np.float64(1.)))
+        self.assertTrue(lib.isscalar(np.int32(1)))
+        self.assertTrue(lib.isscalar(np.object_('foobar')))
+        self.assertTrue(lib.isscalar(np.str_('foobar')))
+        self.assertTrue(lib.isscalar(np.unicode_(u('foobar'))))
+        self.assertTrue(lib.isscalar(np.bytes_(b'foobar')))
+        self.assertTrue(lib.isscalar(np.datetime64('2014-01-01')))
+        self.assertTrue(lib.isscalar(np.timedelta64(1, 'h')))
 
     def test_isscalar_numpy_zerodim_arrays(self):
         for zerodim in [np.array(1),
                         np.array('foobar'),
                         np.array(np.datetime64('2014-01-01')),
                         np.array(np.timedelta64(1, 'h'))]:
-            self.assertFalse(isscalar(zerodim))
-            self.assertTrue(isscalar(item_from_zerodim(zerodim)))
+            self.assertFalse(lib.isscalar(zerodim))
+            self.assertTrue(lib.isscalar(lib.item_from_zerodim(zerodim)))
 
     def test_isscalar_numpy_arrays(self):
-        self.assertFalse(isscalar(np.array([])))
-        self.assertFalse(isscalar(np.array([[]])))
-        self.assertFalse(isscalar(np.matrix('1; 2')))
+        self.assertFalse(lib.isscalar(np.array([])))
+        self.assertFalse(lib.isscalar(np.array([[]])))
+        self.assertFalse(lib.isscalar(np.matrix('1; 2')))
 
     def test_isscalar_pandas_scalars(self):
-        self.assertTrue(isscalar(pd.Timestamp('2014-01-01')))
-        self.assertTrue(isscalar(pd.Timedelta(hours=1)))
-        self.assertTrue(isscalar(pd.Period('2014-01-01')))
-
-    def test_isscalar_pandas_containers(self):
-        self.assertFalse(isscalar(pd.Series()))
-        self.assertFalse(isscalar(pd.Series([1])))
-        self.assertFalse(isscalar(pd.DataFrame()))
-        self.assertFalse(isscalar(pd.DataFrame([[1]])))
-        self.assertFalse(isscalar(pd.Panel()))
-        self.assertFalse(isscalar(pd.Panel([[[1]]])))
-        self.assertFalse(isscalar(pd.Index([])))
-        self.assertFalse(isscalar(pd.Index([1])))
+        self.assertTrue(lib.isscalar(pd.Timestamp('2014-01-01')))
+        self.assertTrue(lib.isscalar(pd.Timedelta(hours=1)))
+        self.assertTrue(lib.isscalar(pd.Period('2014-01-01')))
+
+    def test_lisscalar_pandas_containers(self):
+        self.assertFalse(lib.isscalar(pd.Series()))
+        self.assertFalse(lib.isscalar(pd.Series([1])))
+        self.assertFalse(lib.isscalar(pd.DataFrame()))
+        self.assertFalse(lib.isscalar(pd.DataFrame([[1]])))
+        self.assertFalse(lib.isscalar(pd.Panel()))
+        self.assertFalse(lib.isscalar(pd.Panel([[[1]]])))
+        self.assertFalse(lib.isscalar(pd.Index([])))
+        self.assertFalse(lib.isscalar(pd.Index([1])))
+
+
+if __name__ == '__main__':
+    import nose
+
+    nose.runmodule(argv=[__file__, '-vvs', '-x', '--pdb', '--pdb-failure'],
+                   exit=False)