Merged revisions 60481,60485,60489-60492,60494-60496,60498-60499,60501-60503,60505-60506,60508-60509,60523-60524,60532,60543,60545,60547-60548,60552,60554,60556-60559,60561-60562,60569,60571-60572,60574,60576-60583,60585-60586,60589,60591,60594-60595,60597-60598,60600-60601,60606-60612,60615,60617,60619-60621,60623-60625,60627-60629,60631,60633,60635,60647,60650,60652,60654,60656,60658-60659,60664-60666,60668-60670,60672,60676,60678,60680-60683,60685-60686,60688,60690,60692-60694,60697-60700,60705-60706,60708,60711,60714,60720,60724-60730,60732,60736,60742,60744,60746,60748,60750-60766,60769-60786 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk
........
r60752 | mark.dickinson | 2008-02-12 22:31:59 +0100 (Tue, 12 Feb 2008) | 5 lines
Implementation of Fraction.limit_denominator.
Remove Fraction.to_continued_fraction and
Fraction.from_continued_fraction
........
r60754 | mark.dickinson | 2008-02-12 22:40:53 +0100 (Tue, 12 Feb 2008) | 3 lines
Revert change in r60712: turn alternate constructors back into
classmethods instead of staticmethods.
........
r60755 | mark.dickinson | 2008-02-12 22:46:54 +0100 (Tue, 12 Feb 2008) | 4 lines
Replace R=fractions.Fraction with F=fractions.Fraction in
test_fractions.py. This should have been part of the name
change from Rational to Fraction.
........
r60758 | georg.brandl | 2008-02-13 08:20:22 +0100 (Wed, 13 Feb 2008) | 3 lines
#2063: correct order of utime and stime in os.times()
result on Windows.
........
r60762 | jeffrey.yasskin | 2008-02-13 18:58:04 +0100 (Wed, 13 Feb 2008) | 7 lines
Working on issue #1762: Brought
./python.exe -m timeit -s 'from fractions import Fraction; f = Fraction(3, 2)' 'isinstance(3, Fraction); isinstance(f, Fraction)'
from 12.3 usec/loop to 3.44 usec/loop and
./python.exe -m timeit -s 'from fractions import Fraction' 'Fraction(3, 2)'
from 48.8 usec to 23.6 usec by avoiding genexps and sets in __instancecheck__
and inlining the common case from __subclasscheck__.
........
r60765 | brett.cannon | 2008-02-13 20:15:44 +0100 (Wed, 13 Feb 2008) | 5 lines
Fix --enable-universalsdk and its comment line so that zsh's flag completion
works.
Thanks to Jeroen Ruigrok van der Werven for the fix.
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r60771 | kurt.kaiser | 2008-02-14 01:08:55 +0100 (Thu, 14 Feb 2008) | 2 lines
Bring NEWS.txt up to date from check-in msgs.
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r60772 | raymond.hettinger | 2008-02-14 02:08:02 +0100 (Thu, 14 Feb 2008) | 3 lines
Update notes on Decimal.
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r60773 | raymond.hettinger | 2008-02-14 03:41:22 +0100 (Thu, 14 Feb 2008) | 1 line
Fix decimal repr which should have used single quotes like other reprs.
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r60785 | jeffrey.yasskin | 2008-02-14 07:12:24 +0100 (Thu, 14 Feb 2008) | 11 lines
Performance optimizations on Fraction's constructor.
./python.exe -m timeit -s 'from fractions import Fraction' 'Fraction(3)`
31.7 usec/loop -> 9.2 usec/loop
./python.exe -m timeit -s 'from fractions import Fraction' 'Fraction(3, 2)'`
27.7 usec/loop -> 9.32 usec/loop
./python.exe -m timeit -s 'from fractions import Fraction; f = Fraction(3, 2)' 'Fraction(f)'
31.9 usec/loop -> 14.3 usec/loop
........
r60786 | jeffrey.yasskin | 2008-02-14 08:49:25 +0100 (Thu, 14 Feb 2008) | 5 lines
Change simple instances (in Fraction) of self.numerator and self.denominator to
self._numerator and self._denominator. This speeds abs() up from 12.2us to
10.8us and trunc() from 2.07us to 1.11us. This doesn't change _add and friends
because they're more complicated.
........
diff --git a/Doc/library/decimal.rst b/Doc/library/decimal.rst
index 422436f..afba964 100644
--- a/Doc/library/decimal.rst
+++ b/Doc/library/decimal.rst
@@ -46,10 +46,10 @@
>>> getcontext().prec = 6
>>> Decimal(1) / Decimal(7)
- Decimal("0.142857")
+ Decimal('0.142857')
>>> getcontext().prec = 28
>>> Decimal(1) / Decimal(7)
- Decimal("0.1428571428571428571428571429")
+ Decimal('0.1428571428571428571428571429')
* Both binary and decimal floating point are implemented in terms of published
standards. While the built-in float type exposes only a modest portion of its
@@ -128,19 +128,19 @@
:const:`Infinity`, and :const:`-0`. ::
>>> Decimal(10)
- Decimal("10")
- >>> Decimal("3.14")
- Decimal("3.14")
+ Decimal('10')
+ >>> Decimal('3.14')
+ Decimal('3.14')
>>> Decimal((0, (3, 1, 4), -2))
- Decimal("3.14")
+ Decimal('3.14')
>>> Decimal(str(2.0 ** 0.5))
- Decimal("1.41421356237")
- >>> Decimal(2) ** Decimal("0.5")
- Decimal("1.414213562373095048801688724")
- >>> Decimal("NaN")
- Decimal("NaN")
- >>> Decimal("-Infinity")
- Decimal("-Infinity")
+ Decimal('1.41421356237')
+ >>> Decimal(2) ** Decimal('0.5')
+ Decimal('1.414213562373095048801688724')
+ >>> Decimal('NaN')
+ Decimal('NaN')
+ >>> Decimal('-Infinity')
+ Decimal('-Infinity')
The significance of a new Decimal is determined solely by the number of digits
input. Context precision and rounding only come into play during arithmetic
@@ -148,28 +148,28 @@
>>> getcontext().prec = 6
>>> Decimal('3.0')
- Decimal("3.0")
+ Decimal('3.0')
>>> Decimal('3.1415926535')
- Decimal("3.1415926535")
+ Decimal('3.1415926535')
>>> Decimal('3.1415926535') + Decimal('2.7182818285')
- Decimal("5.85987")
+ Decimal('5.85987')
>>> getcontext().rounding = ROUND_UP
>>> Decimal('3.1415926535') + Decimal('2.7182818285')
- Decimal("5.85988")
+ Decimal('5.85988')
Decimals interact well with much of the rest of Python. Here is a small decimal
floating point flying circus::
>>> data = map(Decimal, '1.34 1.87 3.45 2.35 1.00 0.03 9.25'.split())
>>> max(data)
- Decimal("9.25")
+ Decimal('9.25')
>>> min(data)
- Decimal("0.03")
+ Decimal('0.03')
>>> sorted(data)
- [Decimal("0.03"), Decimal("1.00"), Decimal("1.34"), Decimal("1.87"),
- Decimal("2.35"), Decimal("3.45"), Decimal("9.25")]
+ [Decimal('0.03'), Decimal('1.00'), Decimal('1.34'), Decimal('1.87'),
+ Decimal('2.35'), Decimal('3.45'), Decimal('9.25')]
>>> sum(data)
- Decimal("19.29")
+ Decimal('19.29')
>>> a,b,c = data[:3]
>>> str(a)
'1.34'
@@ -180,31 +180,31 @@
>>> int(a)
1
>>> a * 5
- Decimal("6.70")
+ Decimal('6.70')
>>> a * b
- Decimal("2.5058")
+ Decimal('2.5058')
>>> c % a
- Decimal("0.77")
+ Decimal('0.77')
And some mathematical functions are also available to Decimal::
>>> Decimal(2).sqrt()
- Decimal("1.414213562373095048801688724")
+ Decimal('1.414213562373095048801688724')
>>> Decimal(1).exp()
- Decimal("2.718281828459045235360287471")
- >>> Decimal("10").ln()
- Decimal("2.302585092994045684017991455")
- >>> Decimal("10").log10()
- Decimal("1")
+ Decimal('2.718281828459045235360287471')
+ >>> Decimal('10').ln()
+ Decimal('2.302585092994045684017991455')
+ >>> Decimal('10').log10()
+ Decimal('1')
The :meth:`quantize` method rounds a number to a fixed exponent. This method is
useful for monetary applications that often round results to a fixed number of
places::
>>> Decimal('7.325').quantize(Decimal('.01'), rounding=ROUND_DOWN)
- Decimal("7.32")
+ Decimal('7.32')
>>> Decimal('7.325').quantize(Decimal('1.'), rounding=ROUND_UP)
- Decimal("8")
+ Decimal('8')
As shown above, the :func:`getcontext` function accesses the current context and
allows the settings to be changed. This approach meets the needs of most
@@ -222,16 +222,16 @@
>>> myothercontext = Context(prec=60, rounding=ROUND_HALF_DOWN)
>>> setcontext(myothercontext)
>>> Decimal(1) / Decimal(7)
- Decimal("0.142857142857142857142857142857142857142857142857142857142857")
+ Decimal('0.142857142857142857142857142857142857142857142857142857142857')
>>> ExtendedContext
Context(prec=9, rounding=ROUND_HALF_EVEN, Emin=-999999999, Emax=999999999,
capitals=1, flags=[], traps=[])
>>> setcontext(ExtendedContext)
>>> Decimal(1) / Decimal(7)
- Decimal("0.142857143")
+ Decimal('0.142857143')
>>> Decimal(42) / Decimal(0)
- Decimal("Infinity")
+ Decimal('Infinity')
>>> setcontext(BasicContext)
>>> Decimal(42) / Decimal(0)
@@ -248,7 +248,7 @@
>>> setcontext(ExtendedContext)
>>> getcontext().clear_flags()
>>> Decimal(355) / Decimal(113)
- Decimal("3.14159292")
+ Decimal('3.14159292')
>>> getcontext()
Context(prec=9, rounding=ROUND_HALF_EVEN, Emin=-999999999, Emax=999999999,
capitals=1, flags=[Inexact, Rounded], traps=[])
@@ -261,7 +261,7 @@
context::
>>> Decimal(1) / Decimal(0)
- Decimal("Infinity")
+ Decimal('Infinity')
>>> getcontext().traps[DivisionByZero] = 1
>>> Decimal(1) / Decimal(0)
Traceback (most recent call last):
@@ -289,7 +289,7 @@
Construct a new :class:`Decimal` object based from *value*.
*value* can be an integer, string, tuple, or another :class:`Decimal`
- object. If no *value* is given, returns ``Decimal("0")``. If *value* is a
+ object. If no *value* is given, returns ``Decimal('0')``. If *value* is a
string, it should conform to the decimal numeric string syntax after leading
and trailing whitespace characters are removed::
@@ -307,11 +307,11 @@
If *value* is a :class:`tuple`, it should have three components, a sign
(:const:`0` for positive or :const:`1` for negative), a :class:`tuple` of
digits, and an integer exponent. For example, ``Decimal((0, (1, 4, 1, 4), -3))``
- returns ``Decimal("1.414")``.
+ returns ``Decimal('1.414')``.
The *context* precision does not affect how many digits are stored. That is
determined exclusively by the number of digits in *value*. For example,
- ``Decimal("3.00000")`` records all five zeros even if the context precision is
+ ``Decimal('3.00000')`` records all five zeros even if the context precision is
only three.
The purpose of the *context* argument is determining what to do if *value* is a
@@ -338,7 +338,7 @@
.. method:: Decimal.adjusted()
Return the adjusted exponent after shifting out the coefficient's rightmost
- digits until only the lead digit remains: ``Decimal("321e+5").adjusted()``
+ digits until only the lead digit remains: ``Decimal('321e+5').adjusted()``
returns seven. Used for determining the position of the most significant digit
with respect to the decimal point.
@@ -367,10 +367,10 @@
instance rather than an integer, and if either operand is a NaN
then the result is a NaN::
- a or b is a NaN ==> Decimal("NaN")
- a < b ==> Decimal("-1")
- a == b ==> Decimal("0")
- a > b ==> Decimal("1")
+ a or b is a NaN ==> Decimal('NaN')
+ a < b ==> Decimal('-1')
+ a == b ==> Decimal('0')
+ a > b ==> Decimal('1')
.. method:: Decimal.compare_signal(other[, context])
@@ -389,14 +389,14 @@
value but different representations compare unequal in this
ordering::
- >>> Decimal("12.0").compare_total(Decimal("12"))
- Decimal("-1")
+ >>> Decimal('12.0').compare_total(Decimal('12'))
+ Decimal('-1')
Quiet and signaling NaNs are also included in the total ordering.
- The result of this function is ``Decimal("0")`` if both operands
- have the same representation, ``Decimal("-1")`` if the first
+ The result of this function is ``Decimal('0')`` if both operands
+ have the same representation, ``Decimal('-1')`` if the first
operand is lower in the total order than the second, and
- ``Decimal("1")`` if the first operand is higher in the total order
+ ``Decimal('1')`` if the first operand is higher in the total order
than the second operand. See the specification for details of the
total order.
@@ -428,8 +428,8 @@
Return a copy of the first operand with the sign set to be the
same as the sign of the second operand. For example::
- >>> Decimal("2.3").copy_sign(Decimal("-1.5"))
- Decimal("-2.3")
+ >>> Decimal('2.3').copy_sign(Decimal('-1.5'))
+ Decimal('-2.3')
This operation is unaffected by the context and is quiet: no flags
are changed and no rounding is performed.
@@ -442,9 +442,9 @@
:const:`ROUND_HALF_EVEN` rounding mode.
>>> Decimal(1).exp()
- Decimal("2.718281828459045235360287471")
+ Decimal('2.718281828459045235360287471')
>>> Decimal(321).exp()
- Decimal("2.561702493119680037517373933E+139")
+ Decimal('2.561702493119680037517373933E+139')
.. method:: Decimal.fma(other, third[, context])
@@ -453,7 +453,7 @@
the intermediate product self*other.
>>> Decimal(2).fma(3, 5)
- Decimal("11")
+ Decimal('11')
.. method:: Decimal.is_canonical()
@@ -537,9 +537,9 @@
For a nonzero number, return the adjusted exponent of its operand
as a :class:`Decimal` instance. If the operand is a zero then
- ``Decimal("-Infinity")`` is returned and the
+ ``Decimal('-Infinity')`` is returned and the
:const:`DivisionByZero` flag is raised. If the operand is an
- infinity then ``Decimal("Infinity")`` is returned.
+ infinity then ``Decimal('Infinity')`` is returned.
.. method:: Decimal.logical_and(other[, context])
@@ -620,10 +620,10 @@
.. method:: Decimal.normalize([context])
Normalize the number by stripping the rightmost trailing zeros and converting
- any result equal to :const:`Decimal("0")` to :const:`Decimal("0e0")`. Used for
+ any result equal to :const:`Decimal('0')` to :const:`Decimal('0e0')`. Used for
producing canonical values for members of an equivalence class. For example,
- ``Decimal("32.100")`` and ``Decimal("0.321000e+2")`` both normalize to the
- equivalent value ``Decimal("32.1")``.
+ ``Decimal('32.100')`` and ``Decimal('0.321000e+2')`` both normalize to the
+ equivalent value ``Decimal('32.1')``.
.. method:: Decimal.number_class([context])
@@ -648,8 +648,8 @@
Return a value equal to the first operand after rounding and
having the exponent of the second operand.
- >>> Decimal("1.41421356").quantize(Decimal("1.000"))
- Decimal("1.414")
+ >>> Decimal('1.41421356').quantize(Decimal('1.000'))
+ Decimal('1.414')
Unlike other operations, if the length of the coefficient after the
quantize operation would be greater than precision, then an
@@ -680,7 +680,7 @@
Compute the modulo as either a positive or negative value depending on which is
closest to zero. For instance, ``Decimal(10).remainder_near(6)`` returns
- ``Decimal("-2")`` which is closer to zero than ``Decimal("4")``.
+ ``Decimal('-2')`` which is closer to zero than ``Decimal('4')``.
If both are equally close, the one chosen will have the same sign as *self*.
@@ -732,7 +732,7 @@
Engineering notation has an exponent which is a multiple of 3, so there are up
to 3 digits left of the decimal place. For example, converts
- ``Decimal('123E+1')`` to ``Decimal("1.23E+3")``
+ ``Decimal('123E+1')`` to ``Decimal('1.23E+3')``
.. method:: Decimal.to_integral([rounding[, context]])
@@ -937,10 +937,10 @@
change the result::
>>> getcontext().prec = 3
- >>> Decimal("3.4445") + Decimal("1.0023")
- Decimal("4.45")
- >>> Decimal("3.4445") + Decimal(0) + Decimal("1.0023")
- Decimal("4.44")
+ >>> Decimal('3.4445') + Decimal('1.0023')
+ Decimal('4.45')
+ >>> Decimal('3.4445') + Decimal(0) + Decimal('1.0023')
+ Decimal('4.44')
This method implements the to-number operation of the IBM
specification. If the argument is a string, no leading or trailing
@@ -1195,15 +1195,15 @@
>>> u, v, w = Decimal(11111113), Decimal(-11111111), Decimal('7.51111111')
>>> (u + v) + w
- Decimal("9.5111111")
+ Decimal('9.5111111')
>>> u + (v + w)
- Decimal("10")
+ Decimal('10')
>>> u, v, w = Decimal(20000), Decimal(-6), Decimal('6.0000003')
>>> (u*v) + (u*w)
- Decimal("0.01")
+ Decimal('0.01')
>>> u * (v+w)
- Decimal("0.0060000")
+ Decimal('0.0060000')
The :mod:`decimal` module makes it possible to restore the identities by
expanding the precision sufficiently to avoid loss of significance::
@@ -1211,15 +1211,15 @@
>>> getcontext().prec = 20
>>> u, v, w = Decimal(11111113), Decimal(-11111111), Decimal('7.51111111')
>>> (u + v) + w
- Decimal("9.51111111")
+ Decimal('9.51111111')
>>> u + (v + w)
- Decimal("9.51111111")
+ Decimal('9.51111111')
>>>
>>> u, v, w = Decimal(20000), Decimal(-6), Decimal('6.0000003')
>>> (u*v) + (u*w)
- Decimal("0.0060000")
+ Decimal('0.0060000')
>>> u * (v+w)
- Decimal("0.0060000")
+ Decimal('0.0060000')
Special values
@@ -1275,7 +1275,7 @@
the following calculation returns a value equal to zero::
>>> 1 / Decimal('Infinity')
- Decimal("0E-1000000026")
+ Decimal('0E-1000000026')
.. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -1486,7 +1486,7 @@
>>> D = decimal.Decimal
>>> D('1.23') + D('3.45')
- Decimal("4.68")
+ Decimal('4.68')
Q. In a fixed-point application with two decimal places, some inputs have many
places and need to be rounded. Others are not supposed to have excess digits
@@ -1498,14 +1498,14 @@
>>> TWOPLACES = Decimal(10) ** -2 # same as Decimal('0.01')
>>> # Round to two places
- >>> Decimal("3.214").quantize(TWOPLACES)
- Decimal("3.21")
+ >>> Decimal('3.214').quantize(TWOPLACES)
+ Decimal('3.21')
>>> # Validate that a number does not exceed two places
- >>> Decimal("3.21").quantize(TWOPLACES, context=Context(traps=[Inexact]))
- Decimal("3.21")
+ >>> Decimal('3.21').quantize(TWOPLACES, context=Context(traps=[Inexact]))
+ Decimal('3.21')
- >>> Decimal("3.214").quantize(TWOPLACES, context=Context(traps=[Inexact]))
+ >>> Decimal('3.214').quantize(TWOPLACES, context=Context(traps=[Inexact]))
Traceback (most recent call last):
...
Inexact: Changed in rounding
@@ -1527,7 +1527,7 @@
>>> values = map(Decimal, '200 200.000 2E2 .02E+4'.split())
>>> [v.normalize() for v in values]
- [Decimal("2E+2"), Decimal("2E+2"), Decimal("2E+2"), Decimal("2E+2")]
+ [Decimal('2E+2'), Decimal('2E+2'), Decimal('2E+2'), Decimal('2E+2')]
Q. Some decimal values always print with exponential notation. Is there a way
to get a non-exponential representation?
@@ -1555,7 +1555,7 @@
ctx.prec += 1
>>> float_to_decimal(math.pi)
- Decimal("3.141592653589793115997963468544185161590576171875")
+ Decimal('3.141592653589793115997963468544185161590576171875')
Q. Why isn't the :func:`float_to_decimal` routine included in the module?
@@ -1564,7 +1564,7 @@
representation issues associated with binary floating point::
>>> float_to_decimal(1.1)
- Decimal("1.100000000000000088817841970012523233890533447265625")
+ Decimal('1.100000000000000088817841970012523233890533447265625')
Q. Within a complex calculation, how can I make sure that I haven't gotten a
spurious result because of insufficient precision or rounding anomalies.
@@ -1585,20 +1585,20 @@
>>> getcontext().prec = 3
>>> Decimal('3.104') + D('2.104')
- Decimal("5.21")
+ Decimal('5.21')
>>> Decimal('3.104') + D('0.000') + D('2.104')
- Decimal("5.20")
+ Decimal('5.20')
The solution is either to increase precision or to force rounding of inputs
using the unary plus operation::
>>> getcontext().prec = 3
>>> +Decimal('1.23456789') # unary plus triggers rounding
- Decimal("1.23")
+ Decimal('1.23')
Alternatively, inputs can be rounded upon creation using the
:meth:`Context.create_decimal` method::
>>> Context(prec=5, rounding=ROUND_DOWN).create_decimal('1.2345678')
- Decimal("1.2345")
+ Decimal('1.2345')