|
7.2.3.3 module operations (plural)
+
- addition (concatenation of the generators and simplification)
*
- right or left multiplication with ideal or poly (but not `module` * `module`!)
- module_expression
[ int_expression , int_expression ]
- is a module entry, where the first index indicates the row and
the second the column
- module_expressions
[ int_expression ]
- is a vector, where the index indicates the column (generator)
Example:
| ring A=0,(x,y,z),Dp;
matrix D[3][3];
D[1,2]=-z; D[1,3]=y; D[2,3]=x; // this algebra is U(so_3)
ncalgebra(1,D);
module M = [x,y],[0,0,x*z];
module N = (x+y-z)*M - M*(x+y-z);
print(-N);
==> y+z,0,
==> x-z,0,
==> 0, x2+xy+yz+z2
|
|