cpython/Doc/c-api/number.rst
Georg Brandl e6bcc9145e Remove many "versionchanged" items that didn't use the official markup,
but just some text embedded in the docs.

Also remove paragraph about implicit relative imports from tutorial.
2008-05-12 18:05:20 +00:00

286 lines
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ReStructuredText

.. highlightlang:: c
.. _number:
Number Protocol
===============
.. cfunction:: int PyNumber_Check(PyObject *o)
Returns ``1`` if the object *o* provides numeric protocols, and false otherwise.
This function always succeeds.
.. cfunction:: PyObject* PyNumber_Add(PyObject *o1, PyObject *o2)
Returns the result of adding *o1* and *o2*, or *NULL* on failure. This is the
equivalent of the Python expression ``o1 + o2``.
.. cfunction:: PyObject* PyNumber_Subtract(PyObject *o1, PyObject *o2)
Returns the result of subtracting *o2* from *o1*, or *NULL* on failure. This is
the equivalent of the Python expression ``o1 - o2``.
.. cfunction:: PyObject* PyNumber_Multiply(PyObject *o1, PyObject *o2)
Returns the result of multiplying *o1* and *o2*, or *NULL* on failure. This is
the equivalent of the Python expression ``o1 * o2``.
.. cfunction:: PyObject* PyNumber_Divide(PyObject *o1, PyObject *o2)
Returns the result of dividing *o1* by *o2*, or *NULL* on failure. This is the
equivalent of the Python expression ``o1 / o2``.
.. cfunction:: PyObject* PyNumber_FloorDivide(PyObject *o1, PyObject *o2)
Return the floor of *o1* divided by *o2*, or *NULL* on failure. This is
equivalent to the "classic" division of integers.
.. cfunction:: PyObject* PyNumber_TrueDivide(PyObject *o1, PyObject *o2)
Return a reasonable approximation for the mathematical value of *o1* divided by
*o2*, or *NULL* on failure. The return value is "approximate" because binary
floating point numbers are approximate; it is not possible to represent all real
numbers in base two. This function can return a floating point value when
passed two integers.
.. cfunction:: PyObject* PyNumber_Remainder(PyObject *o1, PyObject *o2)
Returns the remainder of dividing *o1* by *o2*, or *NULL* on failure. This is
the equivalent of the Python expression ``o1 % o2``.
.. cfunction:: PyObject* PyNumber_Divmod(PyObject *o1, PyObject *o2)
.. index:: builtin: divmod
See the built-in function :func:`divmod`. Returns *NULL* on failure. This is
the equivalent of the Python expression ``divmod(o1, o2)``.
.. cfunction:: PyObject* PyNumber_Power(PyObject *o1, PyObject *o2, PyObject *o3)
.. index:: builtin: pow
See the built-in function :func:`pow`. Returns *NULL* on failure. This is the
equivalent of the Python expression ``pow(o1, o2, o3)``, where *o3* is optional.
If *o3* is to be ignored, pass :cdata:`Py_None` in its place (passing *NULL* for
*o3* would cause an illegal memory access).
.. cfunction:: PyObject* PyNumber_Negative(PyObject *o)
Returns the negation of *o* on success, or *NULL* on failure. This is the
equivalent of the Python expression ``-o``.
.. cfunction:: PyObject* PyNumber_Positive(PyObject *o)
Returns *o* on success, or *NULL* on failure. This is the equivalent of the
Python expression ``+o``.
.. cfunction:: PyObject* PyNumber_Absolute(PyObject *o)
.. index:: builtin: abs
Returns the absolute value of *o*, or *NULL* on failure. This is the equivalent
of the Python expression ``abs(o)``.
.. cfunction:: PyObject* PyNumber_Invert(PyObject *o)
Returns the bitwise negation of *o* on success, or *NULL* on failure. This is
the equivalent of the Python expression ``~o``.
.. cfunction:: PyObject* PyNumber_Lshift(PyObject *o1, PyObject *o2)
Returns the result of left shifting *o1* by *o2* on success, or *NULL* on
failure. This is the equivalent of the Python expression ``o1 << o2``.
.. cfunction:: PyObject* PyNumber_Rshift(PyObject *o1, PyObject *o2)
Returns the result of right shifting *o1* by *o2* on success, or *NULL* on
failure. This is the equivalent of the Python expression ``o1 >> o2``.
.. cfunction:: PyObject* PyNumber_And(PyObject *o1, PyObject *o2)
Returns the "bitwise and" of *o1* and *o2* on success and *NULL* on failure.
This is the equivalent of the Python expression ``o1 & o2``.
.. cfunction:: PyObject* PyNumber_Xor(PyObject *o1, PyObject *o2)
Returns the "bitwise exclusive or" of *o1* by *o2* on success, or *NULL* on
failure. This is the equivalent of the Python expression ``o1 ^ o2``.
.. cfunction:: PyObject* PyNumber_Or(PyObject *o1, PyObject *o2)
Returns the "bitwise or" of *o1* and *o2* on success, or *NULL* on failure.
This is the equivalent of the Python expression ``o1 | o2``.
.. cfunction:: PyObject* PyNumber_InPlaceAdd(PyObject *o1, PyObject *o2)
Returns the result of adding *o1* and *o2*, or *NULL* on failure. The operation
is done *in-place* when *o1* supports it. This is the equivalent of the Python
statement ``o1 += o2``.
.. cfunction:: PyObject* PyNumber_InPlaceSubtract(PyObject *o1, PyObject *o2)
Returns the result of subtracting *o2* from *o1*, or *NULL* on failure. The
operation is done *in-place* when *o1* supports it. This is the equivalent of
the Python statement ``o1 -= o2``.
.. cfunction:: PyObject* PyNumber_InPlaceMultiply(PyObject *o1, PyObject *o2)
Returns the result of multiplying *o1* and *o2*, or *NULL* on failure. The
operation is done *in-place* when *o1* supports it. This is the equivalent of
the Python statement ``o1 *= o2``.
.. cfunction:: PyObject* PyNumber_InPlaceDivide(PyObject *o1, PyObject *o2)
Returns the result of dividing *o1* by *o2*, or *NULL* on failure. The
operation is done *in-place* when *o1* supports it. This is the equivalent of
the Python statement ``o1 /= o2``.
.. cfunction:: PyObject* PyNumber_InPlaceFloorDivide(PyObject *o1, PyObject *o2)
Returns the mathematical floor of dividing *o1* by *o2*, or *NULL* on failure.
The operation is done *in-place* when *o1* supports it. This is the equivalent
of the Python statement ``o1 //= o2``.
.. cfunction:: PyObject* PyNumber_InPlaceTrueDivide(PyObject *o1, PyObject *o2)
Return a reasonable approximation for the mathematical value of *o1* divided by
*o2*, or *NULL* on failure. The return value is "approximate" because binary
floating point numbers are approximate; it is not possible to represent all real
numbers in base two. This function can return a floating point value when
passed two integers. The operation is done *in-place* when *o1* supports it.
.. cfunction:: PyObject* PyNumber_InPlaceRemainder(PyObject *o1, PyObject *o2)
Returns the remainder of dividing *o1* by *o2*, or *NULL* on failure. The
operation is done *in-place* when *o1* supports it. This is the equivalent of
the Python statement ``o1 %= o2``.
.. cfunction:: PyObject* PyNumber_InPlacePower(PyObject *o1, PyObject *o2, PyObject *o3)
.. index:: builtin: pow
See the built-in function :func:`pow`. Returns *NULL* on failure. The operation
is done *in-place* when *o1* supports it. This is the equivalent of the Python
statement ``o1 **= o2`` when o3 is :cdata:`Py_None`, or an in-place variant of
``pow(o1, o2, o3)`` otherwise. If *o3* is to be ignored, pass :cdata:`Py_None`
in its place (passing *NULL* for *o3* would cause an illegal memory access).
.. cfunction:: PyObject* PyNumber_InPlaceLshift(PyObject *o1, PyObject *o2)
Returns the result of left shifting *o1* by *o2* on success, or *NULL* on
failure. The operation is done *in-place* when *o1* supports it. This is the
equivalent of the Python statement ``o1 <<= o2``.
.. cfunction:: PyObject* PyNumber_InPlaceRshift(PyObject *o1, PyObject *o2)
Returns the result of right shifting *o1* by *o2* on success, or *NULL* on
failure. The operation is done *in-place* when *o1* supports it. This is the
equivalent of the Python statement ``o1 >>= o2``.
.. cfunction:: PyObject* PyNumber_InPlaceAnd(PyObject *o1, PyObject *o2)
Returns the "bitwise and" of *o1* and *o2* on success and *NULL* on failure. The
operation is done *in-place* when *o1* supports it. This is the equivalent of
the Python statement ``o1 &= o2``.
.. cfunction:: PyObject* PyNumber_InPlaceXor(PyObject *o1, PyObject *o2)
Returns the "bitwise exclusive or" of *o1* by *o2* on success, or *NULL* on
failure. The operation is done *in-place* when *o1* supports it. This is the
equivalent of the Python statement ``o1 ^= o2``.
.. cfunction:: PyObject* PyNumber_InPlaceOr(PyObject *o1, PyObject *o2)
Returns the "bitwise or" of *o1* and *o2* on success, or *NULL* on failure. The
operation is done *in-place* when *o1* supports it. This is the equivalent of
the Python statement ``o1 |= o2``.
.. cfunction:: PyObject* PyNumber_Int(PyObject *o)
.. index:: builtin: int
Returns the *o* converted to an integer object on success, or *NULL* on failure.
If the argument is outside the integer range a long object will be returned
instead. This is the equivalent of the Python expression ``int(o)``.
.. cfunction:: PyObject* PyNumber_Long(PyObject *o)
.. index:: builtin: long
Returns the *o* converted to an integer object on success, or *NULL* on
failure. This is the equivalent of the Python expression ``long(o)``.
.. cfunction:: PyObject* PyNumber_Float(PyObject *o)
.. index:: builtin: float
Returns the *o* converted to a float object on success, or *NULL* on failure.
This is the equivalent of the Python expression ``float(o)``.
.. cfunction:: PyObject* PyNumber_Index(PyObject *o)
Returns the *o* converted to a Python int or long on success or *NULL* with a
TypeError exception raised on failure.
.. cfunction:: PyObject* PyNumber_ToBase(PyObject *n, int base)
Returns the the integer *n* converted to *base* as a string with a base
marker of ``'0b'``, ``'0o'``, or ``'0x'`` if appended applicable. When
*base* is not 2, 8, 10, or 16, the format is ``'x#num'`` where x is the
base. If *n* is not an int object, it is converted with
:cfunc:`PyNumber_Index` first.
.. cfunction:: Py_ssize_t PyNumber_AsSsize_t(PyObject *o, PyObject *exc)
Returns *o* converted to a Py_ssize_t value if *o* can be interpreted as an
integer. If *o* can be converted to a Python int or long but the attempt to
convert to a Py_ssize_t value would raise an :exc:`OverflowError`, then the
*exc* argument is the type of exception that will be raised (usually
:exc:`IndexError` or :exc:`OverflowError`). If *exc* is *NULL*, then the
exception is cleared and the value is clipped to *PY_SSIZE_T_MIN* for a negative
integer or *PY_SSIZE_T_MAX* for a positive integer.
.. cfunction:: int PyIndex_Check(PyObject *o)
Returns True if *o* is an index integer (has the nb_index slot of the
tp_as_number structure filled in).