Function PyArray_DescrFromScalar

numpy/core/src/multiarray/scalarapi.c:531–594

NUMPY_API * Return descr object from array scalar. * * New reference */

 * New reference
 */
NPY_NO_EXPORT PyArray_Descr *
PyArray_DescrFromScalar(PyObject *sc)
{
    int type_num;
    PyArray_Descr *descr;

    if (PyArray_IsScalar(sc, Void)) {
        descr = ((PyVoidScalarObject *)sc)->descr;
        Py_INCREF(descr);
        return descr;
    }

    if (PyArray_IsScalar(sc, Datetime) || PyArray_IsScalar(sc, Timedelta)) {
        PyArray_DatetimeMetaData *dt_data;

        if (PyArray_IsScalar(sc, Datetime)) {
            descr = PyArray_DescrNewFromType(NPY_DATETIME);
        }
        else {
            /* Timedelta */
            descr = PyArray_DescrNewFromType(NPY_TIMEDELTA);
        }
        if (descr == NULL) {
            return NULL;
        }
        dt_data = &(((PyArray_DatetimeDTypeMetaData *)descr->c_metadata)->meta);
        memcpy(dt_data, &((PyDatetimeScalarObject *)sc)->obmeta,
               sizeof(PyArray_DatetimeMetaData));

        return descr;
    }

    descr = PyArray_DescrFromTypeObject((PyObject *)Py_TYPE(sc));
    if (descr == NULL) {
        return NULL;
    }
    if (PyDataType_ISUNSIZED(descr)) {
        PyArray_DESCR_REPLACE(descr);
        if (descr == NULL) {
            return NULL;
        }
        type_num = descr->type_num;
        if (type_num == NPY_STRING) {
            descr->elsize = PyBytes_GET_SIZE(sc);
        }
        else if (type_num == NPY_UNICODE) {
            descr->elsize = PyUnicode_GET_LENGTH(sc) * 4;
        }
        else {
            PyArray_Descr *dtype;
            dtype = (PyArray_Descr *)PyObject_GetAttrString(sc, "dtype");
            if (dtype != NULL) {
                descr->elsize = dtype->elsize;
                descr->fields = dtype->fields;
                Py_XINCREF(dtype->fields);
                descr->names = dtype->names;
                Py_XINCREF(dtype->names);
                Py_DECREF(dtype);