5 REM 3X3 LINEAR SYSTEM (INTEGER RESULTS)
6 REM A=COEFFICIENTS MATRIX; B=KNOWNS VECTOR
7 REM C=INVERTED COEFFICIENTS MATRIX; X=SOLUTIONS VECTOR
8 REM D=REBUILDED KNOWNS VECTOR; E=ERROR VECTOR
9 REM NOTE: VECTORS ARE VERTICAL!
10 LET N=2
20 DATA 1,2,3,-1,2,3,3,1,2,4,-4,-0
30 DIM A(N,N), B(N),C(N,N), X(N),D(N),E(N)
40 MAT READ A,B
50 PRINT "ORIGINAL MATRIX A:"
60 MAT PRINT A
70 PRINT "ORIGINAL VECTOR B:"
80 MAT PRINT B
90 PRINT
100 MAT C=INV(A)
110 IF DET=0 THEN 299
120 MAT X=C*B
130 PRINT "SOLUTION VECTOR X:"
140 MAT PRINT X
150 PRINT
160 MAT D=A*X
170 MAT E=B-D
180 PRINT "ERROR VECTOR E:"
190 MAT PRINT E
290 STOP
299 PRINT "NO SOLUTION POSSIBLE"
300 END

