* The keyboard is assumed to be a MATRIX having 4 rows by 6 columns. However, this code works for any
* MATRIX arrangements up to an 8 x 8 MATRIX. By using from one to three of the column inputs, the driver
* can support "SHIFT" keys. These keys are: SHIFT1, SHIFT2 and SHIFT3.
Initialize U=[uij] MATRIX, U(0)
At k-step: calculate the centers vectors C(k)=[cj] with U(k)
Update U(k) , U(k+1)
If || U(k+1) - U(k)||< then STOP otherwise return to step 2.
