update readme - more consistent docstring

Author: ilanschnell

README.rst

@@ -78,7 +78,7 @@ Once you have installed the package, you may want to test it:
     .........................................................................
     ................................................................
     ----------------------------------------------------------------------
-    Ran 582 tests in 0.165s
+    Ran 587 tests in 0.162s
 
     OK
 
@@ -969,6 +969,13 @@ This sub-module was added in version 1.2.
    iteration is stopped as soon as one mismatch is found.
 
 
+``sum_indices(a, /)`` -> int
+   Return sum of indices of all active bits in bitarray ``a``.
+   This is equivalent to ``sum(i for i, v in enumerate(a) if v)``.
+
+   New in version 3.6
+
+
 ``urandom(n, /, endian=None)`` -> bitarray
    Return random bitarray of length ``n`` (uses ``os.urandom()``).
 
@@ -998,7 +1005,7 @@ This sub-module was added in version 1.2.
 ``xor_indices(a, /)`` -> int
    Return xor reduced indices of all active bits in bitarray ``a``.
    This is essentially equivalent to
-   ``reduce(operator.xor, [i for i, v in enumerate(a) if v])``.
+   ``reduce(operator.xor, (i for i, v in enumerate(a) if v))``.
 
    New in version 3.2
 

bitarray/_util.c

@@ -333,7 +333,7 @@ PyDoc_STRVAR(sum_indices_doc,
 "sum_indices(a, /) -> int\n\
 \n\
 Return sum of indices of all active bits in bitarray `a`.\n\
-This is equivalent to `sum(i for i in range(len(a)) if a[i])`.");
+This is equivalent to `sum(i for i, v in enumerate(a) if v)`.");
 
 
 static PyObject *
@@ -381,7 +381,7 @@ PyDoc_STRVAR(xor_indices_doc,
 \n\
 Return xor reduced indices of all active bits in bitarray `a`.\n\
 This is essentially equivalent to\n\
-`reduce(operator.xor, [i for i, v in enumerate(a) if v])`.");
+`reduce(operator.xor, (i for i, v in enumerate(a) if v))`.");
 
 /* --------------------------- binary functions ------------------------ */
 

bitarray/test_util.py

@@ -1066,7 +1066,7 @@ def test_large(self):
     def test_random(self):
         for a in self.randombitarrays():
             res = sum_indices(a)
-            self.assertEqual(res, sum(i for i in range(len(a)) if a[i]))
+            self.assertEqual(res, sum(i for i, v in enumerate(a) if v))
             self.assertEqual(res, sum(a.search(1)))
 
 # ---------------------------------------------------------------------------
@@ -1081,10 +1081,11 @@ def test_explicit(self):
             self.assertEqual(xor_indices(a), r)
 
     def test_wrong_args(self):
-        self.assertRaises(TypeError, parity, '')
-        self.assertRaises(TypeError, parity, 1)
-        self.assertRaises(TypeError, parity)
-        self.assertRaises(TypeError, parity, bitarray("110"), 1)
+        X = xor_indices
+        self.assertRaises(TypeError, X, '')
+        self.assertRaises(TypeError, X, 1)
+        self.assertRaises(TypeError, X)
+        self.assertRaises(TypeError, X, bitarray("110"), 1)
 
     def test_ones(self):
         # OEIS A003815
@@ -1101,13 +1102,13 @@ def test_ones(self):
 
     def test_random(self):
         for a in self.randombitarrays():
-            indices = [i for i, v in enumerate(a) if v]
-            if len(indices) == 0:
+            cnt = a.count()
+            if cnt == 0:
                 c = 0
-            elif len(indices) == 1:
-                c = indices[0]
+            elif cnt == 1:
+                c = a.index(1)
             else:
-                c = reduce(operator.xor, indices)
+                c = reduce(operator.xor, (i for i, v in enumerate(a) if v))
             self.assertEqual(xor_indices(a), c)
 
     def test_flips(self):

examples/test_random.py

@@ -223,7 +223,7 @@ def test_sums(self):
         # and xor_indices() for large bitarray
         n = 10_000_000
         a = urandom(n, choice(["little", "big"]))
-        indices = [i for i in range(n) if a[i]]
+        indices = [i for i, v in enumerate(a) if v]
         self.assertEqual(sum_indices(a), sum(indices))
         self.assertEqual(xor_indices(a), reduce(operator.xor, indices))