diff --git a/Doc/library/math.rst b/Doc/library/math.rst index be953cfe959948..43eaba935a164a 100644 --- a/Doc/library/math.rst +++ b/Doc/library/math.rst @@ -400,7 +400,8 @@ Trigonometric functions .. function:: dist(p, q) Return the Euclidean distance between two points *p* and *q*, each - given as a tuple of coordinates. The two tuples must be the same size. + given as a sequence (or iterable) of coordinates. The two points + must have the same dimension. Roughly equivalent to:: diff --git a/Lib/test/test_math.py b/Lib/test/test_math.py index 567a5c694c152c..c237bc1942e655 100644 --- a/Lib/test/test_math.py +++ b/Lib/test/test_math.py @@ -833,6 +833,10 @@ def testDist(self): sqrt(sum((px - qx) ** 2.0 for px, qx in zip(p, q))) ) + # Test non-tuple inputs + self.assertEqual(dist([1.0, 2.0, 3.0], [4.0, 2.0, -1.0]), 5.0) + self.assertEqual(dist(iter([1.0, 2.0, 3.0]), iter([4.0, 2.0, -1.0])), 5.0) + # Test allowable types (those with __float__) self.assertEqual(dist((14.0, 1.0), (2.0, -4.0)), 13.0) self.assertEqual(dist((14, 1), (2, -4)), 13) @@ -873,8 +877,6 @@ class T(tuple): dist((1, 2, 3), (4, 5, 6), (7, 8, 9)) with self.assertRaises(TypeError): # Scalars not allowed dist(1, 2) - with self.assertRaises(TypeError): # Lists not allowed - dist([1, 2, 3], [4, 5, 6]) with self.assertRaises(TypeError): # Reject values without __float__ dist((1.1, 'string', 2.2), (1, 2, 3)) with self.assertRaises(ValueError): # Check dimension agree diff --git a/Misc/NEWS.d/next/Library/2019-07-26-22-30-01.bpo-37691.1Li3rx.rst b/Misc/NEWS.d/next/Library/2019-07-26-22-30-01.bpo-37691.1Li3rx.rst new file mode 100644 index 00000000000000..048478c008e806 --- /dev/null +++ b/Misc/NEWS.d/next/Library/2019-07-26-22-30-01.bpo-37691.1Li3rx.rst @@ -0,0 +1,2 @@ +Let math.dist() accept coordinates as sequences (or iterables) rather than +just tuples. diff --git a/Modules/clinic/mathmodule.c.h b/Modules/clinic/mathmodule.c.h index 966b99b6a36900..84561b955787b7 100644 --- a/Modules/clinic/mathmodule.c.h +++ b/Modules/clinic/mathmodule.c.h @@ -297,8 +297,8 @@ PyDoc_STRVAR(math_dist__doc__, "\n" "Return the Euclidean distance between two points p and q.\n" "\n" -"The points should be specified as tuples of coordinates.\n" -"Both tuples must be the same size.\n" +"The points should be specified as sequences (or iterables) of\n" +"coordinates. Both inputs must have the same dimension.\n" "\n" "Roughly equivalent to:\n" " sqrt(sum((px - qx) ** 2.0 for px, qx in zip(p, q)))"); @@ -319,15 +319,7 @@ math_dist(PyObject *module, PyObject *const *args, Py_ssize_t nargs) if (!_PyArg_CheckPositional("dist", nargs, 2, 2)) { goto exit; } - if (!PyTuple_Check(args[0])) { - _PyArg_BadArgument("dist", 1, "tuple", args[0]); - goto exit; - } p = args[0]; - if (!PyTuple_Check(args[1])) { - _PyArg_BadArgument("dist", 2, "tuple", args[1]); - goto exit; - } q = args[1]; return_value = math_dist_impl(module, p, q); @@ -720,4 +712,4 @@ math_comb(PyObject *module, PyObject *const *args, Py_ssize_t nargs) exit: return return_value; } -/*[clinic end generated code: output=0eb1e76a769cdd30 input=a9049054013a1b77]*/ +/*[clinic end generated code: output=f93cfe13ab2fdb4e input=a9049054013a1b77]*/ diff --git a/Modules/mathmodule.c b/Modules/mathmodule.c index 4c1dbbe15ecc22..e1b46ec384a373 100644 --- a/Modules/mathmodule.c +++ b/Modules/mathmodule.c @@ -2427,14 +2427,14 @@ vector_norm(Py_ssize_t n, double *vec, double max, int found_nan) /*[clinic input] math.dist - p: object(subclass_of='&PyTuple_Type') - q: object(subclass_of='&PyTuple_Type') + p: object + q: object / Return the Euclidean distance between two points p and q. -The points should be specified as tuples of coordinates. -Both tuples must be the same size. +The points should be specified as sequences (or iterables) of +coordinates. Both inputs must have the same dimension. Roughly equivalent to: sqrt(sum((px - qx) ** 2.0 for px, qx in zip(p, q))) @@ -2442,16 +2442,34 @@ Roughly equivalent to: static PyObject * math_dist_impl(PyObject *module, PyObject *p, PyObject *q) -/*[clinic end generated code: output=56bd9538d06bbcfe input=937122eaa5f19272]*/ +/*[clinic end generated code: output=56bd9538d06bbcfe input=74e85e1b6092e68e]*/ { PyObject *item; double max = 0.0; double x, px, qx, result; Py_ssize_t i, m, n; - int found_nan = 0; + int found_nan = 0, p_allocated = 0, q_allocated = 0; double diffs_on_stack[NUM_STACK_ELEMS]; double *diffs = diffs_on_stack; + if (!PyTuple_Check(p)) { + p = PySequence_Tuple(p); + if (p == NULL) { + return NULL; + } + p_allocated = 1; + } + if (!PyTuple_Check(q)) { + q = PySequence_Tuple(q); + if (q == NULL) { + if (p_allocated) { + Py_DECREF(p); + } + return NULL; + } + q_allocated = 1; + } + m = PyTuple_GET_SIZE(p); n = PyTuple_GET_SIZE(q); if (m != n) { @@ -2482,12 +2500,24 @@ math_dist_impl(PyObject *module, PyObject *p, PyObject *q) if (diffs != diffs_on_stack) { PyObject_Free(diffs); } + if (p_allocated) { + Py_DECREF(p); + } + if (q_allocated) { + Py_DECREF(q); + } return PyFloat_FromDouble(result); error_exit: if (diffs != diffs_on_stack) { PyObject_Free(diffs); } + if (p_allocated) { + Py_DECREF(p); + } + if (q_allocated) { + Py_DECREF(q); + } return NULL; }