ASKSAGE: Sage Q&A Forum - RSS feedhttps://ask.sagemath.org/questions/Q&A Forum for SageenCopyright Sage, 2010. Some rights reserved under creative commons license.Sat, 04 May 2019 23:02:27 +0200MatrixSpace quotientRingshttps://ask.sagemath.org/question/46448/matrixspace-quotientrings/I'm trying to work with a quotingring of a matrix space. Now I use the following code. But since $n$ is my modulus I expect my second matrix to be equal to $M_1$ in this quotient ring. But it's like its just ignoring the fact that its a quotient ring and it does every computation in MS. What am I doing wrong or is my understanding of quotient rings flawed?
Thanks in advance.
MS = MatrixSpace(ZZ,2,2)
n=MS([[17,19],[11,31]])
R = MS.quotient_ring(MS*n*MS) #or R = MS.quotient_ring(n)
M1 = R([[1,1],[1,1]])
print(M1)
M2 = R(n+M1.lift())
print(M2)
this code gives this as a result
[1 1]
[1 1]
[18 20]
[12 32]Sat, 04 May 2019 17:42:38 +0200https://ask.sagemath.org/question/46448/matrixspace-quotientrings/Comment by John Palmieri for <p>I'm trying to work with a quotingring of a matrix space. Now I use the following code. But since $n$ is my modulus I expect my second matrix to be equal to $M_1$ in this quotient ring. But it's like its just ignoring the fact that its a quotient ring and it does every computation in MS. What am I doing wrong or is my understanding of quotient rings flawed? </p>
<p>Thanks in advance.</p>
<pre><code>MS = MatrixSpace(ZZ,2,2)
n=MS([[17,19],[11,31]])
R = MS.quotient_ring(MS*n*MS) #or R = MS.quotient_ring(n)
M1 = R([[1,1],[1,1]])
print(M1)
M2 = R(n+M1.lift())
print(M2)
</code></pre>
<p>this code gives this as a result</p>
<pre><code>[1 1]
[1 1]
[18 20]
[12 32]
</code></pre>
https://ask.sagemath.org/question/46448/matrixspace-quotientrings/?comment=46451#post-id-46451I think that quotients of matrix rings are not really implemented in Sage in any meaningful way.Sat, 04 May 2019 23:02:27 +0200https://ask.sagemath.org/question/46448/matrixspace-quotientrings/?comment=46451#post-id-46451