Testing math_testcases.txt lacks support for signed zeros #123836

skirpichev · 2024-09-08T11:28:00Z

Feature or enhancement

Proposal:

This file tested, using result_check() helper:

Line 175 in beee91c

def result_check(expected, got, ulp_tol=5, abs_tol=0.0):

which lacks checking of zero sign (while some entries in the data file - have signed zeros). C.f. cmath_testcases.txt, which tested with rAssertAlmostEqual(), that has such special case:

cpython/Lib/test/test_cmath.py

Lines 124 to 131 in beee91c

    
           # if both a and b are zero, check whether they have the same sign 
        
           # (in theory there are examples where it would be legitimate for a 
        
           # and b to have opposite signs; in practice these hardly ever 
        
           # occur). 
        
           if not a and not b: 
        
               if math.copysign(1., a) != math.copysign(1., b): 
        
                   self.fail(msg or 'zero has wrong sign: expected {!r}, ' 
        
                             'got {!r}'.format(a, b))

I think that first helper should be adjusted to do same. I'll work on a patch.

Has this already been discussed elsewhere?

No response given

Links to previous discussion of this feature:

No response

Linked PRs

Just like cmath_testcases.txt. These tests require IEEE 754 anyway.

skirpichev · 2024-09-09T03:46:39Z

PR is ready for review: #123854

Just like cmath_testcases.txt. These tests require IEEE 754 anyway. Correct zero sign for sqrt tests to match math.h convention.

) Just like cmath_testcases.txt. These tests require IEEE 754 anyway. Correct zero sign for sqrt tests to match math.h convention. (cherry picked from commit 28aea5d) Co-authored-by: Sergey B Kirpichev <[email protected]>

vstinner · 2024-09-17T08:24:08Z

Implemented as 28aea5d. Backports will follow.

…124162) gh-123836: Check zero signs in math_testcases.txt (GH-123854) Just like cmath_testcases.txt. These tests require IEEE 754 anyway. Correct zero sign for sqrt tests to match math.h convention. (cherry picked from commit 28aea5d) Co-authored-by: Sergey B Kirpichev <[email protected]>

encukou · 2024-09-17T09:56:10Z

This broke the Windows 10 buildbot: #123854 (comment)

Buildbot failure on Windows 10 with MSC v.1916 64 bit (AMD64): FAIL: testFmod (test.test_math.MathTests.testFmod) ---------------------------------------------------------------------- Traceback (most recent call last): File "D:\buildarea\3.x.bolen-windows10\build\Lib\test\test_math.py", line 605, in testFmod self.ftest('fmod(-10, 1)', math.fmod(-10, 1), -0.0) ~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "D:\buildarea\3.x.bolen-windows10\build\Lib\test\test_math.py", line 258, in ftest self.fail("{}: {}".format(name, failure)) ~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ AssertionError: fmod(-10, 1): expected -0.0, got 0.0 (zero has wrong sign) This amends 28aea5d.

Buildbot failure on Windows 10 with MSC v.1916 64 bit (AMD64): FAIL: testFmod (test.test_math.MathTests.testFmod) ---------------------------------------------------------------------- Traceback (most recent call last): File "D:\buildarea\3.x.bolen-windows10\build\Lib\test\test_math.py", line 605, in testFmod self.ftest('fmod(-10, 1)', math.fmod(-10, 1), -0.0) ~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "D:\buildarea\3.x.bolen-windows10\build\Lib\test\test_math.py", line 258, in ftest self.fail("{}: {}".format(name, failure)) ~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ AssertionError: fmod(-10, 1): expected -0.0, got 0.0 (zero has wrong sign) Here Windows loose sign of the result; if y is nonzero, the result should have the same sign as x. This amends 28aea5d.

skirpichev · 2024-09-17T13:17:00Z

Fix: #124171

Buildbot failure on Windows 10 with MSC v.1916 64 bit (AMD64): FAIL: testFmod (test.test_math.MathTests.testFmod) ---------------------------------------------------------------------- Traceback (most recent call last): File "D:\buildarea\3.x.bolen-windows10\build\Lib\test\test_math.py", line 605, in testFmod self.ftest('fmod(-10, 1)', math.fmod(-10, 1), -0.0) ~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "D:\buildarea\3.x.bolen-windows10\build\Lib\test\test_math.py", line 258, in ftest self.fail("{}: {}".format(name, failure)) ~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ AssertionError: fmod(-10, 1): expected -0.0, got 0.0 (zero has wrong sign) Here Windows loose sign of the result; if y is nonzero, the result should have the same sign as x. This amends commit 28aea5d.

…H-124171) Buildbot failure on Windows 10 with MSC v.1916 64 bit (AMD64): FAIL: testFmod (test.test_math.MathTests.testFmod) ---------------------------------------------------------------------- Traceback (most recent call last): File "D:\buildarea\3.x.bolen-windows10\build\Lib\test\test_math.py", line 605, in testFmod self.ftest('fmod(-10, 1)', math.fmod(-10, 1), -0.0) ~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "D:\buildarea\3.x.bolen-windows10\build\Lib\test\test_math.py", line 258, in ftest self.fail("{}: {}".format(name, failure)) ~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ AssertionError: fmod(-10, 1): expected -0.0, got 0.0 (zero has wrong sign) Here Windows loose sign of the result; if y is nonzero, the result should have the same sign as x. This amends commit 28aea5d. (cherry picked from commit f4dd440) Co-authored-by: Sergey B Kirpichev <[email protected]>

…124186) Buildbot failure on Windows 10 with MSC v.1916 64 bit (AMD64): FAIL: testFmod (test.test_math.MathTests.testFmod) ---------------------------------------------------------------------- Traceback (most recent call last): File "D:\buildarea\3.x.bolen-windows10\build\Lib\test\test_math.py", line 605, in testFmod self.ftest('fmod(-10, 1)', math.fmod(-10, 1), -0.0) ~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "D:\buildarea\3.x.bolen-windows10\build\Lib\test\test_math.py", line 258, in ftest self.fail("{}: {}".format(name, failure)) ~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ AssertionError: fmod(-10, 1): expected -0.0, got 0.0 (zero has wrong sign) Here Windows loose sign of the result; if y is nonzero, the result should have the same sign as x. This amends commit 28aea5d. (cherry picked from commit f4dd440)

Just like cmath_testcases.txt. These tests require IEEE 754 anyway. Correct zero sign for sqrt tests to match math.h convention.

Buildbot failure on Windows 10 with MSC v.1916 64 bit (AMD64): FAIL: testFmod (test.test_math.MathTests.testFmod) ---------------------------------------------------------------------- Traceback (most recent call last): File "D:\buildarea\3.x.bolen-windows10\build\Lib\test\test_math.py", line 605, in testFmod self.ftest('fmod(-10, 1)', math.fmod(-10, 1), -0.0) ~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "D:\buildarea\3.x.bolen-windows10\build\Lib\test\test_math.py", line 258, in ftest self.fail("{}: {}".format(name, failure)) ~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ AssertionError: fmod(-10, 1): expected -0.0, got 0.0 (zero has wrong sign) Here Windows loose sign of the result; if y is nonzero, the result should have the same sign as x. This amends commit 28aea5d.

…124187) Buildbot failure on Windows 10 with MSC v.1916 64 bit (AMD64): FAIL: testFmod (test.test_math.MathTests.testFmod) ---------------------------------------------------------------------- Traceback (most recent call last): File "D:\buildarea\3.x.bolen-windows10\build\Lib\test\test_math.py", line 605, in testFmod self.ftest('fmod(-10, 1)', math.fmod(-10, 1), -0.0) ~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "D:\buildarea\3.x.bolen-windows10\build\Lib\test\test_math.py", line 258, in ftest self.fail("{}: {}".format(name, failure)) ~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ AssertionError: fmod(-10, 1): expected -0.0, got 0.0 (zero has wrong sign) Here Windows loose sign of the result; if y is nonzero, the result should have the same sign as x. This amends commit 28aea5d. (cherry picked from commit f4dd440)

…124161) gh-123836: Check zero signs in math_testcases.txt (GH-123854) Just like cmath_testcases.txt. These tests require IEEE 754 anyway. Correct zero sign for sqrt tests to match math.h convention. (cherry picked from commit 28aea5d) Co-authored-by: Sergey B Kirpichev <[email protected]>

vstinner · 2024-10-16T11:08:23Z

Congrats @skirpichev for this nice enhancement.

skirpichev added the type-feature A feature request or enhancement label Sep 8, 2024

picnixz added the tests Tests in the Lib/test dir label Sep 8, 2024

skirpichev added a commit to skirpichev/cpython that referenced this issue Sep 9, 2024

pythongh-123836: check zero signs in math_testcases.txt

434a1f1

Just like cmath_testcases.txt. These tests require IEEE 754 anyway.

bedevere-app bot mentioned this issue Sep 9, 2024

gh-123836: check zero signs in math_testcases.txt #123854

Merged

vstinner pushed a commit that referenced this issue Sep 17, 2024

gh-123836: Check zero signs in math_testcases.txt (#123854)

28aea5d

Just like cmath_testcases.txt. These tests require IEEE 754 anyway. Correct zero sign for sqrt tests to match math.h convention.

This was referenced Sep 17, 2024

[3.13] gh-123836: Check zero signs in math_testcases.txt (GH-123854) #124161

Merged

[3.12] gh-123836: Check zero signs in math_testcases.txt (GH-123854) #124162

Merged

vstinner closed this as completed Sep 17, 2024

encukou reopened this Sep 17, 2024

bedevere-app bot mentioned this issue Sep 17, 2024

gh-123836: workaround fmod(x, y) bug on Windows #124171

Merged

bedevere-app bot mentioned this issue Sep 17, 2024

[3.12] gh-123836: workaround fmod(x, y) bug on Windows (GH-124171) #124186

Merged

bedevere-app bot mentioned this issue Sep 17, 2024

[3.13] gh-123836: workaround fmod(x, y) bug on Windows (GH-124171) #124187

Merged

zware mentioned this issue Sep 18, 2024

Fix make htmllive target #124219

Merged

skirpichev closed this as completed Oct 16, 2024

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Testing math_testcases.txt lacks support for signed zeros #123836

Testing math_testcases.txt lacks support for signed zeros #123836

skirpichev commented Sep 8, 2024 •

edited by bedevere-app bot

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skirpichev commented Sep 9, 2024

vstinner commented Sep 17, 2024

encukou commented Sep 17, 2024

skirpichev commented Sep 17, 2024

vstinner commented Oct 16, 2024

Testing math_testcases.txt lacks support for signed zeros #123836

Testing math_testcases.txt lacks support for signed zeros #123836

Comments

skirpichev commented Sep 8, 2024 • edited by bedevere-app bot Loading

Feature or enhancement

Proposal:

Has this already been discussed elsewhere?

Links to previous discussion of this feature:

Linked PRs

skirpichev commented Sep 9, 2024

vstinner commented Sep 17, 2024

encukou commented Sep 17, 2024

skirpichev commented Sep 17, 2024

vstinner commented Oct 16, 2024

skirpichev commented Sep 8, 2024 •

edited by bedevere-app bot

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