Function PyUFunc_ReduceWrapper

numpy/core/src/umath/reduction.c:176–462

* This function executes all the standard NumPy reduction function * boilerplate code, just calling the appropriate inner loop function where * necessary. * * context : The ArrayMethod context (with ufunc, method, and descriptors). * operand : The array to be reduced. * out : NULL, or the array into which to place the result. * wheremask : Reduction mask of valid values us

 * generalized ufuncs!)
 */
NPY_NO_EXPORT PyArrayObject *
PyUFunc_ReduceWrapper(PyArrayMethod_Context *context,
        PyArrayObject *operand, PyArrayObject *out, PyArrayObject *wheremask,
        npy_bool *axis_flags, int keepdims,
        PyObject *initial, PyArray_ReduceLoopFunc *loop,
        npy_intp buffersize, const char *funcname, int errormask)
{
    assert(loop != NULL);
    PyArrayObject *result = NULL;
    npy_intp skip_first_count = 0;

    /* Iterator parameters */
    NpyIter *iter = NULL;
    PyArrayObject *op[3];
    PyArray_Descr *op_dtypes[3];
    npy_uint32 it_flags, op_flags[3];
    /* Loop auxdata (must be freed on error) */
    NpyAuxData *auxdata = NULL;

    /* Set up the iterator */
    op[0] = out;
    op[1] = operand;
    op_dtypes[0] = context->descriptors[0];
    op_dtypes[1] = context->descriptors[1];

    /* Buffer to use when we need an initial value */
    char *initial_buf = NULL;

    /* More than one axis means multiple orders are possible */
    if (!(context->method->flags & NPY_METH_IS_REORDERABLE)
            && count_axes(PyArray_NDIM(operand), axis_flags) > 1) {
        PyErr_Format(PyExc_ValueError,
                "reduction operation '%s' is not reorderable, "
                "so at most one axis may be specified",
                funcname);
        goto fail;
    }

    it_flags = NPY_ITER_BUFFERED |
            NPY_ITER_EXTERNAL_LOOP |
            NPY_ITER_GROWINNER |
            NPY_ITER_ZEROSIZE_OK |
            NPY_ITER_REFS_OK |
            NPY_ITER_DELAY_BUFALLOC |
            NPY_ITER_COPY_IF_OVERLAP;
    if (!(context->method->flags & NPY_METH_IS_REORDERABLE)) {
        it_flags |= NPY_ITER_DONT_NEGATE_STRIDES;
    }
    op_flags[0] = NPY_ITER_READWRITE |
                  NPY_ITER_ALIGNED |
                  NPY_ITER_ALLOCATE |
                  NPY_ITER_NO_SUBTYPE;
    op_flags[1] = NPY_ITER_READONLY |
                  NPY_ITER_ALIGNED |
                  NPY_ITER_NO_BROADCAST;

    if (wheremask != NULL) {
        op[2] = wheremask;