BF: deterministic order of slice_time deduction, warning if multiple match

COPYING

@@ -121,36 +121,40 @@ Sphinx 0.6 doesn't work properly.
   OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
   DAMAGE.
 
-Ordereddict
+OrderedSet
 -----------
 
-In ``nibabel/externals/ordereddict.py``
+In ``nibabel/externals/oset.py``
 
-Copied from: https://pypi.python.org/packages/source/o/ordereddict/ordereddict-1.1.tar.gz#md5=a0ed854ee442051b249bfad0f638bbec
+Copied from: https://files.pythonhosted.org/packages/d6/b1/a49498c699a3fda5d635cc1fa222ffc686ea3b5d04b84a3166c4cab0c57b/oset-0.1.3.tar.gz
 
 ::
 
-  Copyright (c) 2009 Raymond Hettinger
-
-  Permission is hereby granted, free of charge, to any person
-  obtaining a copy of this software and associated documentation files
-  (the "Software"), to deal in the Software without restriction,
-  including without limitation the rights to use, copy, modify, merge,
-  publish, distribute, sublicense, and/or sell copies of the Software,
-  and to permit persons to whom the Software is furnished to do so,
-  subject to the following conditions:
-
-      The above copyright notice and this permission notice shall be
-      included in all copies or substantial portions of the Software.
-
-      THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
-      EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
-      OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
-      NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
-      HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
-      WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
-      FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
-      OTHER DEALINGS IN THE SOFTWARE.
+    Copyright (c) 2009, Raymond Hettinger, and others All rights reserved.
+
+    Package structured based on the one developed to odict Copyright (c) 2010, BlueDynamics Alliance, Austria
+
+    - Redistributions of source code must retain the above copyright notice, this
+      list of conditions and the following disclaimer.
+
+    - Redistributions in binary form must reproduce the above copyright notice, this
+      list of conditions and the following disclaimer in the documentation and/or
+      other materials provided with the distribution.
+
+    - Neither the name of the BlueDynamics Alliance nor the names of its
+      contributors may be used to endorse or promote products derived from this
+      software without specific prior written permission.
+
+    THIS SOFTWARE IS PROVIDED BY BlueDynamics Alliance AS IS AND ANY EXPRESS OR
+    IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+    MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+    SHALL BlueDynamics Alliance BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+    SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+    PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+    BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+    CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+    IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+    OF SUCH DAMAGE.
 
 mni_icbm152_t1_tal_nlin_asym_09a
 --------------------------------

nibabel/externals/oset.py

@@ -0,0 +1,85 @@
+# emacs: -*- mode: python-mode; py-indent-offset: 4; indent-tabs-mode: nil -*-
+# vi: set ft=python sts=4 ts=4 sw=4 et:
+### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ##
+#
+#   See COPYING file distributed along with the NiBabel package for the
+#   copyright and license terms.
+#
+### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ##
+"""OrderedSet implementation
+
+Borrowed from https://pypi.org/project/oset/
+Copyright (c) 2009, Raymond Hettinger, and others All rights reserved.
+License: BSD-3
+"""
+
+from __future__ import absolute_import
+
+from collections import MutableSet
+
+KEY, PREV, NEXT = range(3)
+
+
+class OrderedSet(MutableSet):
+
+    def __init__(self, iterable=None):
+        self.end = end = []
+        end += [None, end, end]         # sentinel node for doubly linked list
+        self.map = {}                   # key --> [key, prev, next]
+        if iterable is not None:
+            self |= iterable
+
+    def __len__(self):
+        return len(self.map)
+
+    def __contains__(self, key):
+        return key in self.map
+
+    def __getitem__(self, key):
+        return list(self)[key]
+
+    def add(self, key):
+        if key not in self.map:
+            end = self.end
+            curr = end[PREV]
+            curr[NEXT] = end[PREV] = self.map[key] = [key, curr, end]
+
+    def discard(self, key):
+        if key in self.map:
+            key, prev, next = self.map.pop(key)
+            prev[NEXT] = next
+            next[PREV] = prev
+
+    def __iter__(self):
+        end = self.end
+        curr = end[NEXT]
+        while curr is not end:
+            yield curr[KEY]
+            curr = curr[NEXT]
+
+    def __reversed__(self):
+        end = self.end
+        curr = end[PREV]
+        while curr is not end:
+            yield curr[KEY]
+            curr = curr[PREV]
+
+    def pop(self, last=True):
+        if not self:
+            raise KeyError('set is empty')
+        key = next(reversed(self)) if last else next(iter(self))
+        self.discard(key)
+        return key
+
+    def __repr__(self):
+        if not self:
+            return '%s()' % (self.__class__.__name__,)
+        return '%s(%r)' % (self.__class__.__name__, list(self))
+
+    def __eq__(self, other):
+        if isinstance(other, OrderedSet):
+            return len(self) == len(other) and list(self) == list(other)
+        return set(self) == set(other)
+
+    def __del__(self):
+        self.clear()                    # remove circular references

nibabel/nifti1.py

@@ -1573,14 +1573,23 @@ def set_slice_times(self, slice_times):
         so_recoder = self._field_recoders['slice_code']
         labels = so_recoder.value_set('label')
         labels.remove('unknown')
+
+        matching_labels = []
         for label in labels:
             if np.all(st_order == self._slice_time_order(
                     label,
                     n_timed)):
-                break
-        else:
+                matching_labels.append(label)
+
+        if not matching_labels:
             raise HeaderDataError('slice ordering of %s fits '
                                   'with no known scheme' % st_order)
+        if len(matching_labels) > 1:
+            warnings.warn(
+                'Multiple slice orders satisfy: %s. Choosing the first one'
+                % ', '.join(matching_labels)
+            )
+        label = matching_labels[0]
         # Set values into header
         hdr['slice_start'] = slice_start
         hdr['slice_end'] = slice_end

nibabel/tests/test_nifti1.py

@@ -38,7 +38,12 @@
 from nose.tools import (assert_true, assert_false, assert_equal,
                         assert_raises)
 
-from ..testing import data_path, suppress_warnings, runif_extra_has
+from ..testing import (
+    clear_and_catch_warnings,
+    data_path,
+    runif_extra_has,
+    suppress_warnings,
+)
 
 from . import test_analyze as tana
 from . import test_spm99analyze as tspm
@@ -558,6 +563,22 @@ def test_slice_times(self):
         assert_equal(hdr['slice_end'], 5)
         assert_array_almost_equal(hdr['slice_duration'], 0.1)
 
+        # Ambiguous case
+        hdr2 = self.header_class()
+        hdr2.set_dim_info(slice=2)
+        hdr2.set_slice_duration(0.1)
+        hdr2.set_data_shape((1, 1, 2))
+        with clear_and_catch_warnings() as w:
+            warnings.simplefilter("always")
+            hdr2.set_slice_times([0.1, 0])
+            assert len(w) == 1
+        # but always must be choosing sequential one first
+        assert_equal(hdr2.get_value_label('slice_code'), 'sequential decreasing')
+        # and the other direction
+        hdr2.set_slice_times([0, 0.1])
+        assert_equal(hdr2.get_value_label('slice_code'), 'sequential increasing')
+
+
     def test_intents(self):
         ehdr = self.header_class()
         ehdr.set_intent('t test', (10,), name='some score')

nibabel/volumeutils.py

@@ -13,6 +13,7 @@
 import warnings
 import gzip
 import bz2
+from collections import OrderedDict
 from os.path import exists, splitext
 from operator import mul
 from functools import reduce
@@ -22,6 +23,7 @@
 from .casting import (shared_range, type_info, OK_FLOATS)
 from .openers import Opener
 from .deprecated import deprecate_with_version
+from .externals.oset import OrderedSet
 
 sys_is_le = sys.byteorder == 'little'
 native_code = sys_is_le and '<' or '>'
@@ -78,7 +80,7 @@ class Recoder(object):
     2
     '''
 
-    def __init__(self, codes, fields=('code',), map_maker=dict):
+    def __init__(self, codes, fields=('code',), map_maker=OrderedDict):
         ''' Create recoder object
 
         ``codes`` give a sequence of code, alias sequences
@@ -97,7 +99,7 @@ def __init__(self, codes, fields=('code',), map_maker=dict):
 
         Parameters
         ----------
-        codes : seqence of sequences
+        codes : sequence of sequences
             Each sequence defines values (codes) that are equivalent
         fields : {('code',) string sequence}, optional
             names by which elements in sequences can be accessed
@@ -133,13 +135,15 @@ def add_codes(self, code_syn_seqs):
 
         Examples
         --------
-        >>> code_syn_seqs = ((1, 'one'), (2, 'two'))
+        >>> code_syn_seqs = ((2, 'two'), (1, 'one'))
         >>> rc = Recoder(code_syn_seqs)
         >>> rc.value_set() == set((1,2))
         True
         >>> rc.add_codes(((3, 'three'), (1, 'first')))
         >>> rc.value_set() == set((1,2,3))
         True
+        >>> print(rc.value_set())  # set is actually ordered
+        OrderedSet([2, 1, 3])
         '''
         for code_syns in code_syn_seqs:
             # Add all the aliases
@@ -186,7 +190,7 @@ def keys(self):
         return self.field1.keys()
 
     def value_set(self, name=None):
-        ''' Return set of possible returned values for column
+        ''' Return OrderedSet of possible returned values for column
 
         By default, the column is the first column.
 
@@ -212,7 +216,7 @@ def value_set(self, name=None):
             d = self.field1
         else:
             d = self.__dict__[name]
-        return set(d.values())
+        return OrderedSet(d.values())
 
 
 # Endian code aliases