QR-factorisation via Gram-Schmidt orthogonalization
Random matrix A =
    0.840    0.394    0.783
    0.798    0.912    0.198
    0.335    0.768    0.278
    0.554    0.477    0.629
    0.365    0.513    0.952
Q=
    0.610   -0.602    0.082
    0.580    0.258   -0.580
    0.243    0.704   -0.000
    0.402   -0.061    0.194
    0.265    0.268    0.787
R=(should be right-triangular)
    1.377    1.284    1.165
    0.000    0.647   -0.008
    0.000    0.000    0.821
Q*R= (should be equal the original A)
    0.840    0.394    0.783
    0.798    0.912    0.198
    0.335    0.768    0.278
    0.554    0.477    0.629
    0.365    0.513    0.952
Q^T*Q= (should be equal identity matrix)
    1.000   -0.000   -0.000
   -0.000    1.000   -0.000
   -0.000   -0.000    1.000