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Thank you very much.

How to extract coordinate tuples of homology generators from a simplicial complex? I am working with a simplicial comple

How to extract coordinate tuples of homology generators from a simplicial complex? I am working with a simplicial comple

Thank you very much!

How to extract coordinate tuples of homology generators from a simplicial complex? I am trying to extract the generators

How to extract coordinate tuples of homology generators from a simplicial complex? I am trying to extract the generators

I have a poset $P$ already defined in SageMath. I would like to define a new poset $Q$ on the underlying set of $P$ such that every cover relation of $P$ is a cover relation in $Q$, i.e., I want to add more cover relations in $P$. I got to know that a poset in Sage is immutable (i.e. I can't modify one once it is built). Is it true?

The elements of $P$ are sets ${S_1,\ldots, S_n}$. Assume that the extra cover relation in $Q$ is $S_1$ is covered by $S_2$. I am doing the following to define $Q$:

Rel={ };
for i in P:
      if i==S_1:
          Rel.update({i : P.upper_covers(i) +[S_2]})
      else:
          Rel.update({i : P.upper_covers(i)})
Q = Poset(Rel)

I am getting the following error: TypeError: unhashable type: 'set'

Whereas the following code works:

Rel={ };
for i in P:
     Rel.update({i : P.upper_covers(i)})
Q = Poset(Rel)

Could anyone please help me with this?

Thanks! frozenset worked.

Thanks! $frozenst$ worked.

Adding more cover relations in a poset I have a poset $P$ already defined in SageMath. I would like to define a new pose

Unable to print a poset from Posets(15) I am interested in finding posets with some specific property. To do that, I am

Unable to print a poset from Posets(15) I am interested in finding posets with some specific property. To do that, I am

Thank you. Both of these are working for me.

The command I give is: run "abc.sage" where abc.sage is the file name. I am using SageMath 9.2 on ubuntu 16.04.

I have updated the question.

Unable to use Macaulay2 interface of sage in .sage file I am doing some calculations in sage using Macaulay2 interface.

Unable to use Macaulay2 interface of sage in .sage file I am doing some calculations in sage using Macaulay2 interface.

Unable to use Macaulay2 interface of sage in .sage file I am doing some calculations in sage using Macaulay2 interface.

All posets in P are naturally labelled. That is, for $x, y \in P$ if $x \leq y$ in $P$ then $x \leq y$ in Natural numbers. In this labelling the number of posets that satisfy the given conditions are more then one. So, I don't think that labelling is an issue here.

I want to compute finite posets on 6 elements. Also, I want the following conditions on the posets: 2 covers 0, 4 covers 2, 3 covers 1, 5 covers 3. Also, 0, 1 are incomparable and 4, 5 are incomparable. For that I am giving the following commands:

A=[] 
P = Posets(6)
for p in P:
    if p.covers(0, 2) and p.covers(2, 4) and p.covers(1, 3) and p.covers(3, 5) and p.compare_elements(1, 0) is None and p.compare_elements(4, 5) is None:
        A.append(p);
print(A)

The output I am getting is not correct. There is only one element in sage output but that is not true. Is there any issue with my code?