diff options
Diffstat (limited to 'doc/source/reference/c-api/array.rst')
| -rw-r--r-- | doc/source/reference/c-api/array.rst | 89 |
1 files changed, 17 insertions, 72 deletions
diff --git a/doc/source/reference/c-api/array.rst b/doc/source/reference/c-api/array.rst index 8772b494c..038702bcf 100644 --- a/doc/source/reference/c-api/array.rst +++ b/doc/source/reference/c-api/array.rst @@ -423,7 +423,7 @@ From other objects :c:data:`NPY_ARRAY_FORCECAST` is present in ``flags``, this call will generate an error if the data type cannot be safely obtained from the object. If you want to use - ``NULL`` for the *dtype* and ensure the array is notswapped then + ``NULL`` for the *dtype* and ensure the array is not swapped then use :c:func:`PyArray_CheckFromAny`. A value of 0 for either of the depth parameters causes the parameter to be ignored. Any of the following array flags can be added (*e.g.* using \|) to get the @@ -548,22 +548,6 @@ From other objects :c:data:`NPY_ARRAY_F_CONTIGUOUS` \| :c:data:`NPY_ARRAY_WRITEABLE` \| :c:data:`NPY_ARRAY_ALIGNED` \| :c:data:`NPY_ARRAY_WRITEBACKIFCOPY` -.. c:function:: int PyArray_GetArrayParamsFromObject( \ - PyObject* op, PyArray_Descr* requested_dtype, npy_bool writeable, \ - PyArray_Descr** out_dtype, int* out_ndim, npy_intp* out_dims, \ - PyArrayObject** out_arr, PyObject* context) - - .. deprecated:: NumPy 1.19 - - Unless NumPy is made aware of an issue with this, this function - is scheduled for rapid removal without replacement. - - .. versionchanged:: NumPy 1.19 - - `context` is never used. Its use results in an error. - - .. versionadded:: 1.6 - .. c:function:: PyObject* PyArray_CheckFromAny( \ PyObject* op, PyArray_Descr* dtype, int min_depth, int max_depth, \ int requirements, PyObject* context) @@ -1165,29 +1149,13 @@ Converting data types .. versionadded:: 1.6 - This applies type promotion to all the inputs, - using the NumPy rules for combining scalars and arrays, to - determine the output type of a set of operands. This is the - same result type that ufuncs produce. The specific algorithm - used is as follows. - - Categories are determined by first checking which of boolean, - integer (int/uint), or floating point (float/complex) the maximum - kind of all the arrays and the scalars are. + This applies type promotion to all the input arrays and dtype + objects, using the NumPy rules for combining scalars and arrays, to + determine the output type for an operation with the given set of + operands. This is the same result type that ufuncs produce. - If there are only scalars or the maximum category of the scalars - is higher than the maximum category of the arrays, - the data types are combined with :c:func:`PyArray_PromoteTypes` - to produce the return value. - - Otherwise, PyArray_MinScalarType is called on each array, and - the resulting data types are all combined with - :c:func:`PyArray_PromoteTypes` to produce the return value. - - The set of int values is not a subset of the uint values for types - with the same number of bits, something not reflected in - :c:func:`PyArray_MinScalarType`, but handled as a special case in - PyArray_ResultType. + See the documentation of :func:`numpy.result_type` for more + detail about the type promotion algorithm. .. c:function:: int PyArray_ObjectType(PyObject* op, int mintype) @@ -1202,17 +1170,6 @@ Converting data types return value is the enumerated typenumber that represents the data-type that *op* should have. -.. c:function:: void PyArray_ArrayType( \ - PyObject* op, PyArray_Descr* mintype, PyArray_Descr* outtype) - - This function is superseded by :c:func:`PyArray_ResultType`. - - This function works similarly to :c:func:`PyArray_ObjectType` (...) - except it handles flexible arrays. The *mintype* argument can have - an itemsize member and the *outtype* argument will have an - itemsize member at least as big but perhaps bigger depending on - the object *op*. - .. c:function:: PyArrayObject** PyArray_ConvertToCommonType( \ PyObject* op, int* n) @@ -1490,7 +1447,7 @@ of the constant names is deprecated in 1.7. :c:func:`PyArray_FromAny` and a copy had to be made of some other array (and the user asked for this flag to be set in such a situation). The base attribute then points to the "misbehaved" - array (which is set read_only). :c:func`PyArray_ResolveWritebackIfCopy` + array (which is set read_only). :c:func:`PyArray_ResolveWritebackIfCopy` will copy its contents back to the "misbehaved" array (casting if necessary) and will reset the "misbehaved" array to :c:data:`NPY_ARRAY_WRITEABLE`. If the "misbehaved" array was not @@ -2276,7 +2233,7 @@ Array Functions output array must have the correct shape, type, and be C-contiguous, or an exception is raised. -.. c:function:: PyObject* PyArray_EinsteinSum( \ +.. c:function:: PyArrayObject* PyArray_EinsteinSum( \ char* subscripts, npy_intp nop, PyArrayObject** op_in, \ PyArray_Descr* dtype, NPY_ORDER order, NPY_CASTING casting, \ PyArrayObject* out) @@ -2475,9 +2432,9 @@ As of NumPy 1.6.0, these array iterators are superseded by the new array iterator, :c:type:`NpyIter`. An array iterator is a simple way to access the elements of an -N-dimensional array quickly and efficiently. Section `2 -<#sec-array-iterator>`__ provides more description and examples of -this useful approach to looping over an array. +N-dimensional array quickly and efficiently, as seen in :ref:`the +example <iteration-example>` which provides more description +of this useful approach to looping over an array from C. .. c:function:: PyObject* PyArray_IterNew(PyObject* arr) @@ -3378,7 +3335,7 @@ Memory management .. c:function:: int PyArray_ResolveWritebackIfCopy(PyArrayObject* obj) - If ``obj.flags`` has :c:data:`NPY_ARRAY_WRITEBACKIFCOPY`, this function + If ``obj->flags`` has :c:data:`NPY_ARRAY_WRITEBACKIFCOPY`, this function clears the flags, `DECREF` s `obj->base` and makes it writeable, and sets ``obj->base`` to NULL. It then copies ``obj->data`` to `obj->base->data`, and returns the error state of @@ -3608,29 +3565,17 @@ Miscellaneous Macros Returns the reference count of any Python object. -.. c:function:: void PyArray_DiscardWritebackIfCopy(PyObject* obj) +.. c:function:: void PyArray_DiscardWritebackIfCopy(PyArrayObject* obj) - If ``obj.flags`` has :c:data:`NPY_ARRAY_WRITEBACKIFCOPY`, this function + If ``obj->flags`` has :c:data:`NPY_ARRAY_WRITEBACKIFCOPY`, this function clears the flags, `DECREF` s `obj->base` and makes it writeable, and sets ``obj->base`` to NULL. In - contrast to :c:func:`PyArray_DiscardWritebackIfCopy` it makes no attempt - to copy the data from `obj->base` This undoes + contrast to :c:func:`PyArray_ResolveWritebackIfCopy` it makes no attempt + to copy the data from `obj->base`. This undoes :c:func:`PyArray_SetWritebackIfCopyBase`. Usually this is called after an error when you are finished with ``obj``, just before ``Py_DECREF(obj)``. It may be called multiple times, or with ``NULL`` input. -.. c:function:: void PyArray_XDECREF_ERR(PyObject* obj) - - Deprecated in 1.14, use :c:func:`PyArray_DiscardWritebackIfCopy` - followed by ``Py_XDECREF`` - - DECREF's an array object which may have the - :c:data:`NPY_ARRAY_WRITEBACKIFCOPY` - flag set without causing the contents to be copied back into the - original array. Resets the :c:data:`NPY_ARRAY_WRITEABLE` flag on the base - object. This is useful for recovering from an error condition when - writeback semantics are used, but will lead to wrong results. - Enumerated Types ~~~~~~~~~~~~~~~~ |