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I'm looking for a Sagemath builtin function giving the list of all the possible invariant factors of an abelian group with given finite order (say n)?

In Sagemath terminology, invariant factor is known as elementary divisor

For instance, if n = 48, it should return something like this:

[[2, 2, 2, 6], [2, 2, 12], [2, 24], [4, 12], [48]]

Or perhaps the list of all the possible elementary divisors in the proper sense.

This is not group theory but more or less combinatorics or counting.

Thanks for this code, it handles efficiently groups of order 2**50 (for instance), there are Partitions(50).cardinality(

List of all invariant factors (finite abelian groups) I'm looking for a Sagemath builtin function giving the list of all

List of all invariant factors (finite abelian groups) I'm looking for a Sagemath builtin function giving the list of all

Thanks. I opened an issue

conda-forge install SageMath 9.7 fails I tried to install SageMath 9.7 from conda-forge (my OS is Ubuntu 18.04) followin

Typically, the repr function returns a string that can be executed and yield the same value as the object. In sageMath, this is not the case for a matrix : repr has the same behaviour as the str function has and str applied to a matrix returns a "nice" representation of it:

M=matrix([[1, 1],[1, 1]])

print(repr(M)==str(M)) 
print(M)

printing

True
[1 1]
[1 1]

This is not the behaviour I was expecting. To compare with Numpy:

from numpy import array

M = array([[1, 1], [1, 1]])

print(repr(M))
print()
print(M)

outpouting

array([[1, 1],
       [1, 1]])

[[1 1]
 [1 1]]

Do I need to write my own repr function when applied to a matrix?

`repr` applied on a matrix Typically, the repr function returns a string that can be executed and yield the same value a

Emmanuel, thanks for your detailed examination.

assume causes a solving failure This code var("a b") assume(a, "real") equation=[a+b==0] s=solve(equation, a, b) print(