wiggle_secant2

wiggle_secant2
  Use the secant method to search for a root of the wiggle function.

  F(0.7) = 3.88955
  F(1.2) = -4.36735
2: Estimated convergence rate = 1.40851
3: Estimated convergence rate = 1.55189
4: Estimated convergence rate = 0.26568
5: Estimated convergence rate = 2.21704
6: Estimated convergence rate = 0.649632
7: Estimated convergence rate = 5.83967
8: Estimated convergence rate = 0.956527
9: Estimated convergence rate = 1.91773

  After 9 iterations:
  F(1.03868) = 1.15976e-09

  it <= itmax?  true
  |a-b| <= xtol?  true
  |f(b)| <= ftol?  true
quit