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D.3.2.12 gaussred_pivot
Procedure from library linalg.lib (see linalg_lib).
- Usage:
gaussred_pivot(A); A any constant matrix
- Return:
list Z: Z[1]=P , Z[2]=U , Z[3]=S , Z[4]=rank(A)
gives n row reduced matrix S, a permutation matrix P and a normalized lower triangular matrix U, with P*A=U*S- Note:
with row pivoting
Example:
LIB "linalg.lib"; ring r=0,(x),dp; matrix A[5][4] = 1, 3,-1,4, 2, 5,-1,3, 1, 3,-1,4, 0, 4,-3,1, -3,1,-5,-2; list Z=gaussred_pivot(A); //construct P,U,S s.t. P*A=U*S print(Z[1]); //P print(Z[2]); //U print(Z[3]); //S print(Z[4]); //rank print(Z[1]*A); //P*A print(Z[2]*Z[3]); //U*S |