Merge pull request #14762 from WarrenWeckesser/remove-newdtype-example

MAINT: doc: Remove doc/newdtype_example/

5 files changed, 7 insertions, 192 deletions

diff --git a/doc/newdtype_example/example.py b/doc/newdtype_example/example.py
deleted file mode 100644
index 6be9caa75..000000000
--- a/doc/newdtype_example/example.py
+++ /dev/null
@@ -1,18 +0,0 @@
-from __future__ import division, absolute_import, print_function
-
-import floatint.floatint as ff
-import numpy as np
-
-# Setting using array is hard because
-#  The parser doesn't stop at tuples always
-#  So, the setitem code will be called with scalars on the
-#  wrong shaped array.
-# But we can get a view as an ndarray of the given type:
-g = np.array([1, 2, 3, 4, 5, 6, 7, 8]).view(ff.floatint_type)
-
-# Now, the elements will be the scalar type associated
-#  with the ndarray.
-print(g[0])
-print(type(g[1]))
-
-# Now, you need to register ufuncs and more arrfuncs to do useful things...
diff --git a/doc/newdtype_example/floatint.c b/doc/newdtype_example/floatint.c
deleted file mode 100644
index 0cc198388..000000000
--- a/doc/newdtype_example/floatint.c
+++ /dev/null
@@ -1,152 +0,0 @@
-
-#include "Python.h"
-#include "structmember.h" /* for offset of macro if needed */
-#include "numpy/arrayobject.h"
-
-
-/* Use a Python float as the canonical type being added
-*/
-
-typedef struct _floatint {
-    PyObject_HEAD
-    npy_int32 first;
-    npy_int32 last;
-} PyFloatIntObject;
-
-static PyTypeObject PyFloatInt_Type = {
-    PyObject_HEAD_INIT(NULL)
-    0,                                          /*ob_size*/
-    "floatint.floatint",                        /*tp_name*/
-    sizeof(PyFloatIntObject),                   /*tp_basicsize*/
-};
-
-static PyArray_ArrFuncs _PyFloatInt_Funcs;
-
-#define _ALIGN(type) offsetof(struct {char c; type v;},v)
-
-/* The scalar-type */
-
-static PyArray_Descr _PyFloatInt_Dtype = {
-    PyObject_HEAD_INIT(NULL)
-    &PyFloatInt_Type,
-    'f',
-    '0',
-    '=',
-    0,
-    0,
-    sizeof(double),
-    _ALIGN(double),
-    NULL,
-    NULL,
-    NULL,
-    &_PyFloatInt_Funcs
-};
-
-static void
-twoint_copyswap(void *dst, void *src, int swap, void *arr)
-{
-    if (src != NULL) {
-        memcpy(dst, src, sizeof(double));
-    }
-
-    if (swap) {
-        register char *a, *b, c;
-        a = (char *)dst;
-        b = a + 7;
-        c = *a; *a++ = *b; *b-- = c;
-        c = *a; *a++ = *b; *b-- = c;
-        c = *a; *a++ = *b; *b-- = c;
-        c = *a; *a++ = *b; *b   = c;
-    }
-}
-
-static PyObject *
-twoint_getitem(char *ip, PyArrayObject *ap) {
-    npy_int32 a[2];
- 
-    if ((ap==NULL) || PyArray_ISBEHAVED_RO(ap)) {
-        a[0] = *((npy_int32 *)ip);
-        a[1] = *((npy_int32 *)ip + 1);
-    }
-    else {
-        ap->descr->f->copyswap(a, ip, !PyArray_ISNOTSWAPPED(ap), ap);
-    }
-    return Py_BuildValue("(ii)", a[0], a[1]);
-}
-
-static int
-twoint_setitem(PyObject *op, char *ov, PyArrayObject *ap) {
-    npy_int32 a[2];
-    
-    if (!PyTuple_Check(op)) {
-        PyErr_SetString(PyExc_TypeError, "must be a tuple");
-        return -1;
-    }
-    if (!PyArg_ParseTuple(op, "ii", a, a+1)) return -1;
-
-    if (ap == NULL || PyArray_ISBEHAVED(ap)) {
-        memcpy(ov, a, sizeof(double));
-    }
-    else {
-        ap->descr->f->copyswap(ov, a, !PyArray_ISNOTSWAPPED(ap), ap);
-    }
-    return 0;
-}
-
-static PyArray_Descr * _register_dtype(void)
-{
-    int userval;
-    PyArray_InitArrFuncs(&_PyFloatInt_Funcs); 
-    /* Add copyswap,
-       nonzero, getitem, setitem*/
-    _PyFloatInt_Funcs.copyswap = twoint_copyswap;
-    _PyFloatInt_Funcs.getitem = (PyArray_GetItemFunc *)twoint_getitem;
-    _PyFloatInt_Funcs.setitem = (PyArray_SetItemFunc *)twoint_setitem; 
-    _PyFloatInt_Dtype.ob_type = &PyArrayDescr_Type;
-
-    userval = PyArray_RegisterDataType(&_PyFloatInt_Dtype);
-    return PyArray_DescrFromType(userval);
-}
-
-
-/* Initialization function for the module (*must* be called init<name>) */
-
-PyMODINIT_FUNC initfloatint(void) {
-    PyObject *m, *d;
-    PyArray_Descr *dtype;
-
-    /* Create the module and add the functions */
-    m = Py_InitModule("floatint", NULL);
-
-    /* Import the array objects */
-    import_array();
-
-
-    /* Initialize the new float type */
-    
-    /* Add some symbolic constants to the module */
-    d = PyModule_GetDict(m);
-
-    if (PyType_Ready(&PyFloat_Type) < 0) return;
-    PyFloatInt_Type.tp_base = &PyFloat_Type;
-    /* This is only needed because we are sub-typing the
-       Float type and must pre-set some function pointers
-       to get PyType_Ready to fill in the rest.
-     */
-    PyFloatInt_Type.tp_alloc = PyType_GenericAlloc;
-    PyFloatInt_Type.tp_new = PyFloat_Type.tp_new;
-    PyFloatInt_Type.tp_dealloc = PyFloat_Type.tp_dealloc;
-    PyFloatInt_Type.tp_free = PyObject_Del;
-    if (PyType_Ready(&PyFloatInt_Type) < 0) return;
-    /* End specific code */
-    
-
-    dtype = _register_dtype();
-    Py_XINCREF(dtype);
-    if (dtype != NULL) {
-        PyDict_SetItemString(d, "floatint_type", (PyObject *)dtype);
-    }
-    Py_INCREF(&PyFloatInt_Type);
-    PyDict_SetItemString(d, "floatint", (PyObject *)&PyFloatInt_Type);
-    return;
-}
diff --git a/doc/newdtype_example/floatint/__init__.py b/doc/newdtype_example/floatint/__init__.py
deleted file mode 100644
index 1d0f69b67..000000000
--- a/doc/newdtype_example/floatint/__init__.py
+++ /dev/null
@@ -1 +0,0 @@
-from __future__ import division, absolute_import, print_function
diff --git a/doc/newdtype_example/setup.py b/doc/newdtype_example/setup.py
deleted file mode 100644
index d7ab040a1..000000000
--- a/doc/newdtype_example/setup.py
+++ /dev/null
@@ -1,13 +0,0 @@
-from __future__ import division, print_function
-
-from numpy.distutils.core import setup
-
-def configuration(parent_package = '', top_path=None):
-    from numpy.distutils.misc_util import Configuration
-    config = Configuration('floatint', parent_package, top_path)
-
-    config.add_extension('floatint',
-                         sources = ['floatint.c'])
-    return config
-
-setup(configuration=configuration)
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