MAINT: doc: Refer to _rational_tests.c.src in the user-defined types section.

Also removed a few sentence written in the first person that express
opinions about the code.

1 files changed, 7 insertions, 8 deletions

diff --git a/doc/source/user/c-info.beyond-basics.rst b/doc/source/user/c-info.beyond-basics.rst
index dd25861b4..62e8139fe 100644
--- a/doc/source/user/c-info.beyond-basics.rst
+++ b/doc/source/user/c-info.beyond-basics.rst
@@ -217,14 +217,13 @@ type will behave much like a regular data-type except ufuncs must have
 1-d loops registered to handle it separately. Also checking for
 whether or not other data-types can be cast "safely" to and from this
 new type or not will always return "can cast" unless you also register
-which types your new data-type can be cast to and from. Adding
-data-types is one of the less well-tested areas for NumPy 1.0, so
-there may be bugs remaining in the approach. Only add a new data-type
-if you can't do what you want to do using the OBJECT or VOID
-data-types that are already available. As an example of what I
-consider a useful application of the ability to add data-types is the
-possibility of adding a data-type of arbitrary precision floats to
-NumPy.
+which types your new data-type can be cast to and from.
+
+The NumPy source code includes an example of a custom data-type as part
+of its test suite. The file ``_rational_tests.c.src`` in the source code
+directory  ``numpy/numpy/core/src/umath/`` contains an implementation of
+a data-type that represents a rational number as the ratio of two 32 bit
+integers.
 
 .. index::
    pair: dtype; adding new