D.5.6.1 detadj

Procedure from library mondromy.lib (see mondromy_lib).

Usage:

detadj(U); U matrix

Assume:

U is a square matrix with non zero determinant.

Return:

The procedure returns a list with at most 2 entries.
If U is not a square matrix, the list is empty.
If U is a square matrix, then the first entry is the determinant of U. If U is a square matrix and the determinant of U not zero, then the second entry is the adjoint matrix of U.

Display:

The procedure displays comments if printlevel>=1.

Example:

LIB "mondromy.lib";
ring R=0,x,dp;
matrix U[2][2]=1,1+x,1+x2,1+x3;
list daU=detadj(U);
daU[1];
→ -x2-x
print(daU[2]);
→ x3+1, -x-1,
→ -x2-1,1