Maybe I misunderstood your question about indexed variables, you do
can create and use arrays of oovars and oofuns, eg
from FuncDesigner import *
N = 100
a = oovars(N) # create array of N oovars
b = oovars(N) # another array of N oovars
some_lin_funcs = [i*a[i]+4*i + 5*b[i] for i in xrange(N)]
f = some_lin_funcs[15] + some_lin_funcs[80]
point = {}
for i in xrange(N):
point[a[i]] = 1.5 * i**2
point[b[i]] = 1.5 * i**3
print f(point)
print a[15](point)
print some_lin_funcs[25](point)
# [ 4638755.]
# [ 337.5]
# [ 140725.]
Regards, D.
On Aug 26, 11:04 pm, Nathann Cohen <nathann.co...@gmail.com> wrote:
> > Yes, you can use indexation like some_oovar[i] or some_oofun[i]
> > (probably with several indexes, or negative ones that are start from
> > array end), however, I think it should be avoided if possible (you'd
> > better split your oovar into several
> > oovars).http://www.openopt.org/FuncDesignerDoc#Some_issues_to_be_aware
>
> I sent a message on sage-support to know to which extent I could use
> multivariate Polynomials in Sage to represent constraints and Linear
> functions, but it seems to be troublesome... This said, there is no
> way for me to use Linear Programming if I can not use indexed
> variables... At the moment, even though the syntax could be
> tremendously improved, I can use any hashable Sage object as a
> variable, and most of the time in Graph theoretic function my
> variables are edges, vertices, or arbitrary tuples and strings.
> Anyway, most of the Linear Programs are generated from graphs and I
> have to find a way to let a computer create as many variables as
> possible :-/
> The current syntax, though, is not nearly satisfying.
>
> > Maybe I have translated it wrong with my small knowledge of English.
>
> I'm french. We bear the same cross ;-)
>
> > I had awared of OSI, but I'm not skilled in connecting code of other
> > languages to Python, that's why I hadn't go for it.
>
> > This is very nice to hear, still I think it would be better to provide
> > Python-OSI API instead of SAGE-OSI, it would benefit more wield
> > auditory (PythonXY, EPD, mere Python-scipy users etc). Of course, it's
> > up to you - mb you are SAGE developer at first.
>
> I'm sorry to give you this "cheap" an answer, but if anyone wants to
> write such code, it will always be available as it is GPL-Licensed. I
> am not particularly interested in LP, I just began to write these
> interfaces because I thought the Graph functions I needed would be
> much harder to write otherwise, and often less effective. I just wrote
> a shortcut. Now, if LP can be of independent interest in Sage, why not
> spending some time over it as I know how it works ?
> Besides, in Sage I only have to care about the stuff that interests
> me... If I need symbolics, plots, interfaces, I can ask people whose
> interest lies there and they'll give me answer, sometimes solutions.
> If they need anything dealing with Graphs, I'll do what I can.
> Pretty naive, but so relieving :-)
>
> Regards,
>
> Nathann
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