Function NpyIter_EnableExternalLoop

numpy/core/src/multiarray/nditer_api.c:192–232

NUMPY_API * Removes the inner loop handling (so HasExternalLoop returns true) */

 * Removes the inner loop handling (so HasExternalLoop returns true)
 */
NPY_NO_EXPORT int
NpyIter_EnableExternalLoop(NpyIter *iter)
{
    npy_uint32 itflags = NIT_ITFLAGS(iter);
    /*int ndim = NIT_NDIM(iter);*/
    int nop = NIT_NOP(iter);

    /* Check conditions under which this can be done */
    if (itflags&(NPY_ITFLAG_HASINDEX|NPY_ITFLAG_HASMULTIINDEX)) {
        PyErr_SetString(PyExc_ValueError,
                "Iterator flag EXTERNAL_LOOP cannot be used "
                "if an index or multi-index is being tracked");
        return NPY_FAIL;
    }
    if ((itflags&(NPY_ITFLAG_BUFFER|NPY_ITFLAG_RANGE|NPY_ITFLAG_EXLOOP))
                        == (NPY_ITFLAG_RANGE|NPY_ITFLAG_EXLOOP)) {
        PyErr_SetString(PyExc_ValueError,
                "Iterator flag EXTERNAL_LOOP cannot be used "
                "with ranged iteration unless buffering is also enabled");
        return NPY_FAIL;
    }
    /* Set the flag */
    if (!(itflags&NPY_ITFLAG_EXLOOP)) {
        itflags |= NPY_ITFLAG_EXLOOP;
        NIT_ITFLAGS(iter) = itflags;

        /*
         * Check whether we can apply the single iteration
         * optimization to the iternext function.
         */
        if (!(itflags&NPY_ITFLAG_BUFFER)) {
            NpyIter_AxisData *axisdata = NIT_AXISDATA(iter);
            if (NIT_ITERSIZE(iter) == NAD_SHAPE(axisdata)) {
                NIT_ITFLAGS(iter) |= NPY_ITFLAG_ONEITERATION;
            }
        }
    }

    /* Reset the iterator */
    return NpyIter_Reset(iter, NULL);
}


static char *_reset_cast_error = (