#16804: points() has problems with some lists of complexes containing real (i.e
imag(x==0)) values.
-------------------------------+-------------------------------------------
Reporter: charpent | Owner:
Type: defect | Status: new
Priority: minor | Milestone:
Component: graphics | Keywords: graphics, plot, complex
Merged in: | Authors: Emmanuel Charpentier
Reviewers: | Report Upstream: N/A
Work issues: | Branch:
Commit: | Dependencies:
Stopgaps: cast points to |
CC |
-------------------------------+-------------------------------------------
Motivating example :
`sage: points(map(lambda x:x[0].N(),(z^20+1).roots()), figsize=4,
aspect_ratio=1)` works as expected.
`sage: points(map(lambda x:x[0].N(),(z^20-1).roots()), figsize=4,
aspect_ratio=1)` gives an error.
One (namely K. Crisman ) notes ([https://groups.google.com/forum/#!topic
/sage-support/uyiSDTxQ_2U]) that some of the member of the second set are
real (namely -1 and 1) while none of the members of the first set is real.
Indeed :
`points(map(N, [1+I,I,I-1,-1-I,-I,1-I]),figsize=4)` works as expected.
`points(map(N, [0,1,1+I,I,I-1,-1,-1-I,-I,1-I]),figsize=4)` gives an error.
One also notes that `points([1+I,I,I-1,-1-I,-I,1-I],figsize=4)` while
conforming to `points()` documentation, gives another, different error.
Workaround suggested by K. Crisman :
`sage: points(map(lambda x:CC(x[0].N()),(z^20-1).roots()), figsize=4,
aspect_ratio=1)` works as expected.
--
Ticket URL: <http://trac.sagemath.org/ticket/16804>
Sage <http://www.sagemath.org>
Sage: Creating a Viable Open Source Alternative to Magma, Maple, Mathematica,
and MATLAB
--
You received this message because you are subscribed to the Google Groups
"sage-trac" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
To post to this group, send email to [email protected].
Visit this group at http://groups.google.com/group/sage-trac.
For more options, visit https://groups.google.com/d/optout.
