This seems to be more than an inefficiency but rather a bug that causes it
to never stop. I ran the code on an AWS machine and it consumed *360GB *of
RAM by now. (and is still running.)
How can I report it as a bug?
On Wednesday, 25 April 2018 23:35:07 UTC+3, Emanuel Sygal wrote:
>
> Hi, thanks for the suggestion.
> Using DenseMatrix did not seem to rectify the problem.
> I attach a .txt file containing the matrix as a list of tuples, to help
> reproducing. I do not know how to file a bug formally.
> (Does this also happen to you?)
>
> The file can be loaded, e.g., by the commands
> with open("vectors_list.txt", "rb") as f:
> x = eval(f.read())
> A = sympy.SparseMatrix(x)
> y = A.nullspace()
>
>
> On Wednesday, 25 April 2018 21:27:10 UTC+3, Aaron Meurer wrote:
>>
>> This should probably be considered a bug. Most likely our nullspace
>> algorithm is doing something inefficient.
>>
>> Since your matrix is mostly zeros, you might try using a sparse matrix
>> (SparseMatrix).
>>
>> Aaron Meurer
>>
>> On Wed, Apr 25, 2018 at 10:41 AM, Emanuel Sygal <[email protected]>
>> wrote:
>> > I am trying to find a basis for the nullspace of some matrix $A$ in
>> sympy of
>> > size (384, 120). When calling
>> > A.nullspace()
>> > The RAM usage gradually rises up to the 60GB that I have, and then the
>> > kernel dies.The matrix consists of elements that are just 1,-1,0 and
>> mostly
>> > zero.I create the matix like this:
>> > A = sympy.Matrix(vectors_list)
>> >
>> > where every element of vectors_list is a tuple of elements of type
>> > sympy.core.numbers.I tried setting the environment variables
>> > "SYMPY_USE_CACHE", "SYMPY_INT_TRACE" to "no"
>> > and it did not make a change.
>> >
>> > I also posted here:
>> >
>> https://stackoverflow.com/questions/49997220/sympy-memory-explosion-when-computing-nullspace-of-a-small-matrix?noredirect=1#
>>
>> > without luck. What can I do more?
>> >
>> > --
>> > You received this message because you are subscribed to the Google
>> Groups
>> > "sympy" group.
>> > To unsubscribe from this group and stop receiving emails from it, send
>> an
>> > email to [email protected].
>> > To post to this group, send email to [email protected].
>> > Visit this group at https://groups.google.com/group/sympy.
>> > To view this discussion on the web visit
>> >
>> https://groups.google.com/d/msgid/sympy/4b5bb5ee-2a42-4489-b062-22c4a3098e90%40googlegroups.com.
>>
>>
>> > For more options, visit https://groups.google.com/d/optout.
>>
>
--
You received this message because you are subscribed to the Google Groups
"sympy" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
To post to this group, send email to [email protected].
Visit this group at https://groups.google.com/group/sympy.
To view this discussion on the web visit
https://groups.google.com/d/msgid/sympy/fede5d50-ff44-4b07-bd60-ab0da830b9e3%40googlegroups.com.
For more options, visit https://groups.google.com/d/optout.
