bisect_test
  Test bisect()
  X =   1.00000000  f(x) =  -0.100000E+01
  X =   2.00000000  f(x) =   0.500000E+01
  X =   1.50000000  f(x) =   0.875000E+00
  X =   1.25000000  f(x) =  -0.296875E+00
  X =   1.37500000  f(x) =   0.224609E+00
  X =   1.31250000  f(x) =  -0.515137E-01
  X =   1.34375000  f(x) =   0.826111E-01
  X =   1.32812500  f(x) =   0.145760E-01
  X =   1.32031250  f(x) =  -0.187106E-01
  X =   1.32421875  f(x) =  -0.212795E-02
  X =   1.32617188  f(x) =   0.620878E-02
  X =   1.32519531  f(x) =   0.203669E-02
  X =   1.32470703  f(x) =  -0.466108E-04
  X =   1.32495117  f(x) =   0.994682E-03
  X =   1.32482910  f(x) =   0.473976E-03
  X =   1.32476807  f(x) =   0.213742E-03
  X =   1.32473755  f(x) =   0.835657E-04
  X =   1.32472229  f(x) =   0.184774E-04
  X =   1.32471466  f(x) =  -0.140071E-04
  X =   1.32471848  f(x) =   0.214577E-05
  X =   1.32471657  f(x) =  -0.590086E-05

  Estimated zero is x =   1.32471752
  with error bound   0.953674E-06