Hello,
-it would be a good idea to warn the user if some results may be wrong due
> to the used ring. Perhaps this deserves a ticket on its own.
>
+1
> -use is_positive for non exact ring
>
I do not understand the aim of that.
-Perhaps containment should be done combinatorially in the case
On Wednesday, October 14, 2015 at 8:27:44 AM UTC+2, jplab wrote:
>
> -it would be a good idea to warn the user if some results may be wrong due
> to the used ring. Perhaps this deserves a ticket on its own.
>
I think thats a bit silly; really it is just a special case of "any result
in RDF might
On Wed, Oct 14, 2015 at 4:26 AM, Volker Braun wrote:
> On Wednesday, October 14, 2015 at 8:27:44 AM UTC+2, jplab wrote:
>>
>> -it would be a good idea to warn the user if some results may be wrong
>> due to the used ring. Perhaps this deserves a ticket on its own.
>>
>
> I think thats a bit silly
The following used to work (based on regular private doctesting outside of
Sage source code) and give you the path you wanted:
P9 = Graph([[0..8], lambda i,j: i-j == 1])
Now it silently produces an empty graph (9 vertices, no edges). The fix:
P9 = Graph([[0..8], lambda i,j: i-j == -1])
Is thi
I would rather use
P9 = Graph([[0..8], lambda i,j: abs(i-j) == 1])
since edges have no reason to be ordered with i>j or i
The following used to work (based on regular private doctesting outside of
Sage source code) and give you the path you wanted:
P9 = Graph([[0..8], lambda i,j: i-j == 1])
Well, the first thing I tried was (i-j)^2 == 1. ;-)
Partially answering my own question, by reading the code (graphs/graph.py):
from itertools import combinations
self.add_vertices(verts)
self.add_edges(e for e in combinations(verts,2) if f(*e))
self.add_edges((v,v) for v in verts if f(v,v))
Hello,
Sorry for the change in behaviour, perhaps I should write somewhere that
'f' must be symmetric. I could do so in #19390, for it actually cleans the
constructor code and their documentation.
So should the "edge-detection" function be required to return true for any
> pair of vertices joi
