 f = 9.606440e-01 f-delta = 1.6e-03
 Iter 52: f = 9.621834e-01 f-delta = 1.5e-03
 Iter 53: f = 9.636167e-01 f-delta = 1.4e-03
 Iter 54: f = 9.649394e-01 f-delta = 1.3e-03
 Iter 55: f = 9.661493e-01 f-delta = 1.2e-03
 Iter 56: f = 9.672469e-01 f-delta = 1.1e-03
 Iter 57: f = 9.682348e-01 f-delta = 9.9e-04
 Iter 58: f = 9.691174e-01 f-delta = 8.8e-04
 Iter 59: f = 9.699007e-01 f-delta = 7.8e-04
 Iter 60: f = 9.705915e-01 f-delta = 6.9e-04
 Iter 61: f = 9.711975e-01 f-delta = 6.1e-04
 Iter 62: f = 9.717263e-01