A minor 
is the reduced determinant
of a determinant expansion that
is formed by omitting the 
th
row and 
th column of a matrix 
. So, for example, the minor 
of the above matrix is given by
 |
The 
th minor can be computed in the Wolfram Language using
Minor[m_List?MatrixQ, {i_Integer, j_Integer}] :=
Det[Drop[Transpose[Drop[Transpose[m], {j}]],
{i}]]
The Wolfram Language's built-in Minors[m]
command instead gives the minors of a matrix 
obtained by deleting the 
st row and 
st column of 
, while Minors[m,
k] gives the 
th
minors of 
. The Minor code above therefore
corresponds to 
th
entry of
MinorMatrix[m_List?MatrixQ] := Map[Reverse,
Minors[m], {0, 1}]
i.e., the definition Minors[m, 
i, j
] is equivalent to MinorMatrix[m][[i,
j]].
Lichtblau, D. "Symbolic FAQ."