diff options
Diffstat (limited to 'doc/source/reference/c-api.ufunc.rst')
| -rw-r--r-- | doc/source/reference/c-api.ufunc.rst | 23 |
1 files changed, 14 insertions, 9 deletions
diff --git a/doc/source/reference/c-api.ufunc.rst b/doc/source/reference/c-api.ufunc.rst index ece6cc391..02a35cf56 100644 --- a/doc/source/reference/c-api.ufunc.rst +++ b/doc/source/reference/c-api.ufunc.rst @@ -93,15 +93,20 @@ Functions the corresponding 1-d loop function in the func array. :param types: - Int8 of length `(nin + nout) * ntypes` It encodes the :ref:`dtype.num` - (built-in only) that the corresponding function in the `func` array - accepts. For a ufunc with two `ntypes`, one `nin` and one `nout` where - the first function accepts and returns `int32` and the second accepts - and returns `int64`, `types` would be `\05\05\07\07` since `int32.num` - is 5 and `int64.num` is 7. - - :ref:`casting-rules` will be used at runtime to find the first `func` callable - by the input/output provided. + Length ``(nin + nout) * ntypes`` array of ``char`` encoding the + :ref:`PyArray_Descr.type_num` (built-in only) that the corresponding + function in the ``func`` array accepts. For instance, for a comparison + ufunc with three ``ntypes``, two ``nin`` and one ``nout``, where the + first function accepts :ref:`npy_int32` and the the second + :ref:`npy_int64`, with both returning :ref:`npy_bool`, ``types`` would + be ``(char[]) {5, 5, 0, 7, 7, 0}`` since ``NPY_INT32`` is 5, + ``NPY_INT64`` is 7, and ``NPY_BOOL`` is 0 (on the python side, these + are exposed via :ref:`dtype.num`, i.e., for the example here, + ``dtype(np.int32).num``, ``dtype(np.int64).num``, and + ``dtype(np.bool_).num``, resp.). + + :ref:`casting-rules` will be used at runtime to find the first + ``func`` callable by the input/output provided. :param ntypes: How many different data-type-specific functions the ufunc has implemented. |