C:FOCAL-11,TEST 1.05 ERASE 1.10 A !"FAST MATRIX INVERSION. SIZE OF MATRIX? "N,!"ENTER ELEMENTS. 1.20 S LAST=N*N 1.40 FOR J=1,N;T !;F I=J,N,LAST-N+J;A A(I) 1.50 T !"ORIGINAL:"!;D 4 1.60 DO 2 1.70 T !"INVERSE:"!;D 4 1.80 D 2 1.90 T !"INVERSE(INVERSE):"!;D 4 1.95 QUIT 2.05 C INVERT MATRIX 2.10 FOR J=1,N; DO 6 4.05 C PRINT MATRIX 4.60 F Z=1,N;T %2,"ROW "Z;S NC=0;F I=Z,N,LAST-N+Z;DO 5 4.70 T !! 5.10 T " "%7.06,,A(I) 5.20 S NC=NC+1;IF (NC-4)5.7;T !;S NC=0 5.70 R 6.10 FOR I=1,N;S A(LAST+I)=0 6.20 S A(LAST+J)=1 6.30 CLEAR PIVOT ROW 6.40 I (A(J))6.5,9.01; 6.50 F KP=J+N,N,LAST+J;S A(KP)=A(KP)/A(J) 6.60 CALCULATE REMAINING ROWS. 6.70 FOR KR=1,N;D 7 6.80 C SHIFT ARRAY TO ELIMINATE LEADING UNIT VECTOR. 6.90 FOR I=1,LAST; S A(I)=A(I+N) 7.10 I (KR-J)7.4,5.7; 7.40 S KP=J 7.50 S RW=A(KR) 7.60 FOR Q=KR+N,N,LAST+KR;S KP=KP+N; S A(Q)=A(Q)-RW*A(KP);D 8 8.10 IF (1E-5-FABS(A(Q)))8.2;S A(Q)=0 8.20 R 9.01 T "FOR "?J?," INTERCHANGE PLEASE."!;QUIT * K ?