### The Tits form

The Tits form **q**_{a} is an integral quadratic form associated
with an algebra **a**. In particular, **q**_{a} is a linear
map from **Z**^{n} to the integers **Z** where n is the number
of vertices in the quiver of the algebra **a**. Such a quadratic form is
represented in CREP by its integral symmetric coefficient matrix, ie a matrix
Q with integral coefficients and the property
**q**_{a}(x) = x^{T} Q x for any vector x in
**Z**^{n}.
The function 'titsform' calculates the corresponding matrix for a
given bound poset algebra. This matrix in our example being of size
54 x 54 we display only part of the function's output:

Back to the worksheet of the example session.

* Last modified: 04-03-1998 *