nag_lapacklin_zptrfs (f07jvc) Example Program Data 4 2 : n, nrhs 16.0 41.0 46.0 21.0 : diagonal d ( 16.0, 16.0) ( 18.0, -9.0) ( 1.0, -4.0) : sub-diagonal e ( 64.0, 16.0) (-16.0,-32.0) ( 93.0, 62.0) ( 61.0,-66.0) ( 78.0,-80.0) ( 71.0,-74.0) ( 14.0,-27.0) ( 35.0, 15.0) : matrix B