Function PyUFunc_GenericFunctionInternal

numpy/core/src/umath/ufunc_object.c:2657–2749

static int
PyUFunc_GenericFunctionInternal(PyUFuncObject *ufunc,
        PyArrayMethodObject *ufuncimpl, PyArray_Descr *operation_descrs[],
        PyArrayObject *op[], PyObject *extobj,
        NPY_CASTING casting, NPY_ORDER order,
        PyObject *output_array_prepare[], ufunc_full_args full_args,
        PyArrayObject *wheremask)
{
    int nin = ufunc->nin, nout = ufunc->nout, nop = nin + nout;

    const char *ufunc_name = ufunc_get_name_cstr(ufunc);

    npy_intp default_op_out_flags;
    npy_uint32 op_flags[NPY_MAXARGS];

    /* These parameters come from extobj= or from a TLS global */
    int buffersize = 0, errormask = 0;

    NPY_UF_DBG_PRINT1("\nEvaluating ufunc %s\n", ufunc_name);

    /* Get the buffersize and errormask */
    if (_get_bufsize_errmask(extobj, ufunc_name, &buffersize, &errormask) < 0) {
        return -1;
    }

    if (wheremask != NULL) {
        /* Set up the flags. */
        default_op_out_flags = NPY_ITER_NO_SUBTYPE |
                               NPY_ITER_WRITEMASKED |
                               NPY_UFUNC_DEFAULT_OUTPUT_FLAGS;
        _ufunc_setup_flags(ufunc, NPY_UFUNC_DEFAULT_INPUT_FLAGS,
                           default_op_out_flags, op_flags);
    }
    else {
        /* Set up the flags. */
        default_op_out_flags = NPY_ITER_WRITEONLY |
                               NPY_UFUNC_DEFAULT_OUTPUT_FLAGS;
        _ufunc_setup_flags(ufunc, NPY_UFUNC_DEFAULT_INPUT_FLAGS,
                           default_op_out_flags, op_flags);
    }

    /* Final preparation of the arraymethod call */
    PyArrayMethod_Context context = {
        .caller = (PyObject *)ufunc,
        .method = ufuncimpl,
        .descriptors = operation_descrs,
    };

    /* Do the ufunc loop */
    if (wheremask != NULL) {
        NPY_UF_DBG_PRINT("Executing masked inner loop\n");

        if (nop + 1 > NPY_MAXARGS) {
            PyErr_SetString(PyExc_ValueError,
                    "Too many operands when including where= parameter");
            return -1;
        }
        op[nop] = wheremask;