Function PyArray_PutMask

numpy/core/src/multiarray/item_selection.c:632–762

NUMPY_API * Put values into an array according to a mask. */

 * Put values into an array according to a mask.
 */
NPY_NO_EXPORT PyObject *
PyArray_PutMask(PyArrayObject *self, PyObject* values0, PyObject* mask0)
{
    PyArrayObject *mask, *values;
    PyArray_Descr *dtype;
    npy_intp itemsize, ni, nv;
    char *src, *dest;
    npy_bool *mask_data;
    int copied = 0;
    int overlap = 0;
    NPY_BEGIN_THREADS_DEF;

    mask = NULL;
    values = NULL;
    if (!PyArray_Check(self)) {
        PyErr_SetString(PyExc_TypeError,
                        "putmask: first argument must "
                        "be an array");
        return NULL;
    }

    if (PyArray_FailUnlessWriteable(self, "putmask: output array") < 0) {
        return NULL;
    }

    mask = (PyArrayObject *)PyArray_FROM_OTF(mask0, NPY_BOOL,
                                NPY_ARRAY_CARRAY | NPY_ARRAY_FORCECAST);
    if (mask == NULL) {
        goto fail;
    }
    ni = PyArray_SIZE(mask);
    if (ni != PyArray_SIZE(self)) {
        PyErr_SetString(PyExc_ValueError,
                        "putmask: mask and data must be "
                        "the same size");
        goto fail;
    }
    mask_data = PyArray_DATA(mask);
    dtype = PyArray_DESCR(self);
    Py_INCREF(dtype);
    values = (PyArrayObject *)PyArray_FromAny(values0, dtype,
                                    0, 0, NPY_ARRAY_CARRAY, NULL);
    if (values == NULL) {
        goto fail;
    }
    nv = PyArray_SIZE(values); /* zero if null array */
    if (nv <= 0) {
        Py_XDECREF(values);
        Py_XDECREF(mask);
        Py_RETURN_NONE;
    }
    src = PyArray_DATA(values);

    overlap = arrays_overlap(self, values) || arrays_overlap(self, mask);
    if (overlap || !PyArray_ISCONTIGUOUS(self)) {
        int flags = NPY_ARRAY_CARRAY | NPY_ARRAY_WRITEBACKIFCOPY;
        PyArrayObject *obj;