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Merge pull request #262 from python/master
bpo-39648: Expand math.gcd() and math.lcm() to handle multiple argume…
2 parents 0ad3f0f + 559e7f1 commit 389031f

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Lines changed: 171 additions & 175 deletions

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‎Doc/library/math.rst‎

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@@ -126,23 +126,19 @@ Number-theoretic and representation functions
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<https://code.activestate.com/recipes/393090/>`_\.
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.. function:: gcd(a, b)
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.. function:: gcd(*integers)
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Return the greatest common divisor of the integers *a* and *b*. If either
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*a* or *b* is nonzero, then the value of ``gcd(a, b)`` is the largest
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positive integer that divides both *a* and *b*. ``gcd(0, 0)`` returns
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``0``.
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Return the greatest common divisor of the specified integer arguments.
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If any of the arguments is nonzero, then the returned value is the largest
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positive integer that is a divisor af all arguments. If all arguments
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are zero, then the returned value is ``0``. ``gcd()`` without arguments
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returns ``0``.
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.. versionadded:: 3.5
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.. function:: lcm(a, b)
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Return the least common multiple of integers *a* and *b*. The value of
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``lcm(a, b)`` is the smallest nonnegative integer that is a multiple of
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both *a* and *b*. If either *a* or *b* is zero then ``lcm(a, b)`` is zero.
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.. versionadded:: 3.9
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.. versionchanged:: 3.9
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Added support for an arbitrary number of arguments. Formerly, only two
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arguments were supported.
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.. function:: isclose(a, b, *, rel_tol=1e-09, abs_tol=0.0)
@@ -210,6 +206,17 @@ Number-theoretic and representation functions
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.. versionadded:: 3.8
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.. function:: lcm(*integers)
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Return the least common multiple of the specified integer arguments.
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If all arguments are nonzero, then the returned value is the smallest
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positive integer that is a multiple of all arguments. If any of the arguments
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is zero, then the returned value is ``0``. ``lcm()`` without arguments
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returns ``1``.
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.. versionadded:: 3.9
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.. function:: ldexp(x, i)
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Return ``x * (2**i)``. This is essentially the inverse of function

‎Doc/whatsnew/3.9.rst‎

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@@ -216,8 +216,13 @@ import attempts.
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math
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----
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Add :func:`math.lcm`: return the least common multiple of *a* and *b*.
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(Contributed by Ananthakrishnan in :issue:`39479`.)
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Expanded the :func:`math.gcd` function to handle multiple arguments.
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Formerly, it only supported two arguments.
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(Contributed by Serhiy Storchaka in :issue:`39648`.)
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Add :func:`math.lcm`: return the least common multiple of specified arguments.
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(Contributed by Mark Dickinson, Ananthakrishnan and Serhiy Storchaka in
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:issue:`39479` and :issue:`39648`.)
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Add :func:`math.nextafter`: return the next floating-point value after *x*
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towards *y*.

‎Lib/test/test_math.py‎

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Original file line numberDiff line numberDiff line change
@@ -705,33 +705,32 @@ def testGcd(self):
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self.assertEqual(gcd(84, -120), 12)
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self.assertEqual(gcd(1216342683557601535506311712,
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436522681849110124616458784), 32)
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c = 652560
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x = 434610456570399902378880679233098819019853229470286994367836600566
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y = 1064502245825115327754847244914921553977
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a = x * c
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b = y * c
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self.assertEqual(gcd(a, b), c)
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self.assertEqual(gcd(b, a), c)
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self.assertEqual(gcd(-a, b), c)
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self.assertEqual(gcd(b, -a), c)
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self.assertEqual(gcd(a, -b), c)
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self.assertEqual(gcd(-b, a), c)
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self.assertEqual(gcd(-a, -b), c)
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self.assertEqual(gcd(-b, -a), c)
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c = 576559230871654959816130551884856912003141446781646602790216406874
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a = x * c
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b = y * c
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self.assertEqual(gcd(a, b), c)
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self.assertEqual(gcd(b, a), c)
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self.assertEqual(gcd(-a, b), c)
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self.assertEqual(gcd(b, -a), c)
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self.assertEqual(gcd(a, -b), c)
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self.assertEqual(gcd(-b, a), c)
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self.assertEqual(gcd(-a, -b), c)
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self.assertEqual(gcd(-b, -a), c)
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for c in (652560,
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576559230871654959816130551884856912003141446781646602790216406874):
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a = x * c
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b = y * c
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self.assertEqual(gcd(a, b), c)
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self.assertEqual(gcd(b, a), c)
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self.assertEqual(gcd(-a, b), c)
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self.assertEqual(gcd(b, -a), c)
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self.assertEqual(gcd(a, -b), c)
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self.assertEqual(gcd(-b, a), c)
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self.assertEqual(gcd(-a, -b), c)
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self.assertEqual(gcd(-b, -a), c)
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self.assertEqual(gcd(), 0)
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self.assertEqual(gcd(120), 120)
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self.assertEqual(gcd(-120), 120)
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self.assertEqual(gcd(120, 84, 102), 6)
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self.assertEqual(gcd(120, 1, 84), 1)
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self.assertRaises(TypeError, gcd, 120.0)
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self.assertRaises(TypeError, gcd, 120.0, 84)
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self.assertRaises(TypeError, gcd, 120, 84.0)
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self.assertRaises(TypeError, gcd, 120, 1, 84.0)
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self.assertEqual(gcd(MyIndexable(120), MyIndexable(84)), 12)
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def testHypot(self):
@@ -989,9 +988,9 @@ def test_lcm(self):
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self.assertEqual(lcm(1216342683557601535506311712,
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436522681849110124616458784),
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16592536571065866494401400422922201534178938447014944)
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x = 43461045657039990237
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y = 10645022458251153277
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for c in (652560,
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57655923087165495981):
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a = x * c
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self.assertEqual(lcm(-b, a), d)
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self.assertEqual(lcm(-a, -b), d)
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self.assertEqual(lcm(-b, -a), d)
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self.assertEqual(lcm(MyIndexable(120), MyIndexable(84)), 840)
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1008+
self.assertEqual(lcm(), 1)
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self.assertEqual(lcm(120), 120)
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self.assertEqual(lcm(-120), 120)
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self.assertEqual(lcm(120, 84, 102), 14280)
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self.assertEqual(lcm(120, 0, 84), 0)
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self.assertRaises(TypeError, lcm, 120.0)
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self.assertRaises(TypeError, lcm, 120.0, 84)
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self.assertRaises(TypeError, lcm, 120, 84.0)
1017+
self.assertRaises(TypeError, lcm, 120, 0, 84.0)
1018+
self.assertEqual(lcm(MyIndexable(120), MyIndexable(84)), 840)
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10121020
def testLdexp(self):
10131021
self.assertRaises(TypeError, math.ldexp)

‎Misc/NEWS.d/next/Library/2020-02-22-12-49-04.bpo-39648.Y-9N7F.rst‎

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Expanded :func:`math.gcd` and :func:`math.lcm` to handle multiple arguments.

‎Modules/clinic/mathmodule.c.h‎

Lines changed: 1 addition & 61 deletions
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