# Revision history [back]

### Creating a matrix that has elements part of a GF

I am currently doing some implementation but I have something that I do not seem to find online and bugged me for a few hours:

e = 48; K = GF(2^e); KE = GF(2^(e*2));

A = matrix(KE,3,3); E11 = 24; E12 = 59; E21 = 21; E23 = 28; E32 = 29; E33 = 65; A[0,0] = 2^E11; A[0,1] = 2^E12; A[0,2] = 0; A[1,0] = 2^E21; A[1,1] = 0; A[1,2] = 2^E23; A[2,0] = 0; A[2,1] = 2^E32; A[2,2] = 2^E33;

print A[2][1]

When I do this, it print 0, but given that I created it in GF(2^(e*2)), I believe it shouldn't. Because of this, when I try to get the inverse of this matrix, which is invertible, I do not get anything. Please let me know if you have any thoughts.

 2 None tmonteil 27023 ●30 ●196 ●508 http://wiki.sagemath.o...

### Creating a matrix that has elements part of a GF

I am currently doing some implementation but I have something that I do not seem to find online and bugged me for a few hours:

e = 48;
K = GF(2^e);
KE = GF(2^(e*2));GF(2^(e*2));
A = matrix(KE,3,3);
E11 = 24;
E12 = 59;
E21 = 21;
E23 = 28;
E32 = 29;
E33 = 65;
A[0,0] = 2^E11;
A[0,1] = 2^E12;
A[0,2] = 0;
A[1,0] = 2^E21;
A[1,1] = 0;
A[1,2] = 2^E23;
A[2,0] = 0;
A[2,1] = 2^E32;
A[2,2] = 2^E33;2^E33;
print A[2][1]A[2][1]


When I do this, it print 0, but given that I created it in GF(2^(e*2)), I believe it shouldn't. Because of this, when I try to get the inverse of this matrix, which is invertible, I do not get anything. Please let me know if you have any thoughts.