[pypy-commit] pypy numpypy-is_contiguous: test, implement is_contiguous for C order

[mattip]

Author: mattip
Branch: numpypy-is_contiguous
Changeset: r50225:b8c87c4cf664
Date: 2011-12-06 22:14 +0200
http://bitbucket.org/pypy/pypy/changeset/b8c87c4cf664/

Log:	test, implement is_contiguous for C order

diff --git a/pypy/module/micronumpy/interp_numarray.py b/pypy/module/micronumpy/interp_numarray.py
--- a/pypy/module/micronumpy/interp_numarray.py
+++ b/pypy/module/micronumpy/interp_numarray.py
@@ -155,6 +155,27 @@
             last_step *= shape[i]
     return steps
 
+def is_contiguous(arr):
+    #Only views can be non-contiguous
+    if isinstance(arr, ViewArray):
+        steps = calc_steps(arr.shape, arr.strides)
+        for i in range(1, len(steps)):
+            if steps[i] != steps[0]:
+                return False
+    return True
+
+def is_contiguous_lr(arr):
+    if arr.strides[-1] < arr.strides[0]:
+        #rl, not lr
+        return False
+    return is_contiguous(arr)
+
+def is_contiguous_rl(self):
+    if arr.strides[-1] > arr.strides[0]:
+        #lr, not rl
+        return False
+    return is_contiguous(arr)
+
 #Recalculating strides. Find the steps that the iteration does for each
 #dimension, given the stride and shape. Then try to create a new stride that
 #fits the new shape, using those steps. If there is a shape/step mismatch
@@ -192,7 +213,8 @@
         n_new_elems_used = 1
         oldI = -1
         n_old_elems_to_use = old_shape[-1]
-        for s in new_shape[::-1]:
+        for i in range(len(new_shape) - 1, -1, -1):
+            s = new_shape[i]
             new_strides.insert(0, cur_step * n_new_elems_used)
             n_new_elems_used *= s
             while n_new_elems_used > n_old_elems_to_use:
diff --git a/pypy/module/micronumpy/test/test_numarray.py b/pypy/module/micronumpy/test/test_numarray.py
--- a/pypy/module/micronumpy/test/test_numarray.py
+++ b/pypy/module/micronumpy/test/test_numarray.py
@@ -166,6 +166,23 @@
         assert calc_new_strides([24], [2, 4, 3], [48, 6, 1]) is None
         assert calc_new_strides([24], [2, 4, 3], [24, 6, 2]) == [2]
 
+    def test_contiguousC(self):
+        from pypy.module.micronumpy.interp_numarray import is_contiguous,
+            is_contiguous_rl, is_contiguous_lr
+        a = W_NDimArray(10 * 5 * 3, [10, 5, 3], MockDtype(), 'C')
+        assert is_contiguous(a) == True
+        assert is_contiguous_lr(a) == False
+        assert is_contiguous_rl(a) == True
+        b = a.descr_get_transpose(self.space)
+        assert is_contiguous(b) == True
+        assert is_contiguous_lr(b) == True
+        assert is_contiguous_rl(b) == False
+        b = a.create_slice(self.space, [(0, 10, 2, 5)])
+        assert is_contiguous(b) == False
+        assert is_contiguous_lr(b) == False
+        assert is_contiguous_rl(b) == False
+        
+
 class AppTestNumArray(BaseNumpyAppTest):
     def test_ndarray(self):
         from numpypy import ndarray, array, dtype