On 21/02/2019 9:59, Jori Mäntysalo (TAU) wrote:
On Tue, 19 Feb 2019, TB wrote:
There is the cardinality method of IntegerVectors. Note that the default for
min_part is 0.
So this could be used for...?
I do not know the area. I was just playing with numbers (original question
was "In how many
One example where enumeration of these (with say a fixed sum) is useful is
for computing ordered set partitions by breaking the problem up into sets
of fixed sizes.
Best,
Travis
On Thursday, February 21, 2019 at 5:59:56 PM UTC+10, Jori Mäntysalo (TAU)
wrote:
>
> On Tue, 19 Feb 2019, TB wrote:
On Tue, 19 Feb 2019, TB wrote:
> There is the cardinality method of IntegerVectors. Note that the default for
> min_part is 0.
So this could be used for...?
I do not know the area. I was just playing with numbers (original question
was "In how many ways you can arrange a queue of 9 men and 7 w
There is the cardinality method of IntegerVectors. Note that the default
for min_part is 0.
It is implemented in src/sage/combinat/integer_vector.py without brute
force enumeration under some constraints. Looking at it now, I think
there is a bug at line 1331: It will never enter the if clause
I am guessing that it should be sufficiently fast to compute the
cardinality using the generating series. That is, for compositions with
parts in a set S this would be
1/(1-sum_{s in S} x^s)
with special cases S = {a,...,b} and S = {a,...}
Martin
Am Dienstag, 19. Februar 2019 22:03:43 UTC+1
I do think that P = Partitions(15, min_length=10, max_length=10);
P.cardinality() also uses brute force. (at least P.cardinality?? says so).
Would be great, though!
Martin
Am Dienstag, 19. Februar 2019 21:43:36 UTC+1 schrieb Jori Mäntysalo (TAU):
>
> Is there a fast way to compute for example
