nag_dpprfs (f07ghc) Example Program Results

 Solution(s)
            1          2
 1      1.0000     4.0000
 2     -1.0000     3.0000
 3      2.0000     2.0000
 4     -3.0000     1.0000

Backward errors (machine-dependent)
    6.7e-17     7.9e-17 
Estimated forward error bounds (machine-dependent)
    2.3e-14     2.3e-14