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i doesn't belong to QQbar ? Why ?

asked 2017-11-12 20:55:13 +0200

Emmanuel Charpentier gravatar image

updated 2017-11-13 10:30:54 +0200

tmonteil gravatar image

I do not understand this :

sage: sqrt(1) in QQbar
sage: sqrt(-2) in QQbar
sage: sqrt(-1) in QQbar

Can someone explain ?

Note that, however :

sage: [t[0] in QQbar for t in (x^2+1).roots(ring=QQbar)]
[True, True]
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answered 2017-11-13 01:12:08 +0200

tmonteil gravatar image

updated 2017-11-13 01:12:45 +0200

This is definitely a bug, thanks for reporting! As you can see in the source code:

sage: QQbar.__contains__??

the test:

 elif EQ:

which corresponds to:

sage: bool(I == QQbar(I))

leads to:

TypeError: unsupported operand parent(s) for +: 'Number Field in I with defining polynomial x^2 + 1' and 'Algebraic Field'

which is catched to return False.

I have opened trac ticket 24209 for this.

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answered 2018-08-03 14:46:47 +0200

Javidlg gravatar image

Still the same bug on SageMath version 8.2, Release Date: 2018-05-05 . Nobody fix this? 0.0

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1) This is not an answer...

2) see the mentioned ticket (as well as thetickets it refers to) to understand why there is not quick-and-easy fix for this one...

Emmanuel Charpentier gravatar imageEmmanuel Charpentier ( 2018-08-03 21:08:11 +0200 )edit

@Emmanuel Charpentier thanks for 1), my mistake. I decided to move back to linux, so my comment doesnt have sense anymore. Thanks for the feedback!

Javidlg gravatar imageJavidlg ( 2019-03-04 16:13:09 +0200 )edit

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Asked: 2017-11-12 20:55:13 +0200

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Last updated: Aug 03 '18