Function _PyArray_ArgMinMaxCommon

numpy/core/src/multiarray/calculation.c:39–196

}

NPY_NO_EXPORT PyObject *
_PyArray_ArgMinMaxCommon(PyArrayObject *op,
        int axis, PyArrayObject *out, int keepdims,
        npy_bool is_argmax)
{
    PyArrayObject *ap = NULL, *rp = NULL;
    PyArray_ArgFunc* arg_func = NULL;
    char *ip, *func_name;
    npy_intp *rptr;
    npy_intp i, n, m;
    int elsize;
    // Keep a copy because axis changes via call to PyArray_CheckAxis
    int axis_copy = axis;
    npy_intp _shape_buf[NPY_MAXDIMS];
    npy_intp *out_shape;
    // Keep the number of dimensions and shape of
    // original array. Helps when `keepdims` is True.
    npy_intp* original_op_shape = PyArray_DIMS(op);
    int out_ndim = PyArray_NDIM(op);
    NPY_BEGIN_THREADS_DEF;

    if ((ap = (PyArrayObject *)PyArray_CheckAxis(op, &axis, 0)) == NULL) {
        return NULL;
    }
    /*
     * We need to permute the array so that axis is placed at the end.
     * And all other dimensions are shifted left.
     */
    if (axis != PyArray_NDIM(ap)-1) {
        PyArray_Dims newaxes;
        npy_intp dims[NPY_MAXDIMS];
        int j;

        newaxes.ptr = dims;
        newaxes.len = PyArray_NDIM(ap);
        for (j = 0; j < axis; j++) {
            dims[j] = j;
        }
        for (j = axis; j < PyArray_NDIM(ap) - 1; j++) {
            dims[j] = j + 1;
        }
        dims[PyArray_NDIM(ap) - 1] = axis;
        op = (PyArrayObject *)PyArray_Transpose(ap, &newaxes);
        Py_DECREF(ap);
        if (op == NULL) {
            return NULL;
        }
    }
    else {
        op = ap;
    }

    // Will get native-byte order contiguous copy.
    PyArray_Descr *descr = NPY_DT_CALL_ensure_canonical(PyArray_DESCR(op));
    if (descr == NULL) {
        return NULL;
    }
    ap = (PyArrayObject *)PyArray_FromArray(op, descr, NPY_ARRAY_DEFAULT);