Problem using confidence interval with genpareto distribution

[cehiles]

Hello,

I previously used wafo under Matlab but I am now migrating to python.

The issue I am currently encountering occurs when I attempt to plot a genpareto distribution with confidence intervals. My script and the terminal response is below. The last line of the response just keeps repeating until I kill it. There are a lot of warnings in the response and I am having trouble teasing out where this error is originating. It may have something to do with that fact that I am running a newer version of Python than WAFO was tested with (Anaconda, Python 3.6). Any suggestions on where to go from here would be greatly appreciated.

Thanks,

Clayton

My script:

import matplotlib.pyplot as plt
import wafo.data as wd
from wafo import stats as ws
plt.ioff()

Hs = wd.atlantic()
gpd3 = ws.genpareto.fit2(Hs[Hs>3],floc=3)
fig, axes = plt.subplots()
gpd3.plotesf(plot_ci=True)
plt.show()

Terminal response:

$ python test_wafo_genpar_ci.py 
/home/clayton/anaconda3/envs/wafo/lib/python3.6/site-packages/wafo/stats/estimation.py:1553: UserWarning: P-value is on the conservative side (i.e. too large) due to ties in the data!
  ' ties in the data!')
QApplication: invalid style override passed, ignoring it.
/home/clayton/anaconda3/envs/wafo/lib/python3.6/site-packages/wafo/stats/estimation.py:122: RuntimeWarning: invalid value encountered in double_scalars
  return (x - loc) * c / expm1(-c * logsf)
/home/clayton/anaconda3/envs/wafo/lib/python3.6/site-packages/wafo/stats/_distn_infrastructure.py:490: RuntimeWarning: invalid value encountered in greater_equal
  return (self.a <= x) & (x <= self.b)
/home/clayton/anaconda3/envs/wafo/lib/python3.6/site-packages/wafo/stats/_distn_infrastructure.py:490: RuntimeWarning: invalid value encountered in less_equal
  return (self.a <= x) & (x <= self.b)
/home/clayton/anaconda3/envs/wafo/lib/python3.6/site-packages/numpy/core/fromnumeric.py:83: RuntimeWarning: invalid value encountered in reduce
  return ufunc.reduce(obj, axis, dtype, out, **passkwargs)
/home/clayton/anaconda3/envs/wafo/lib/python3.6/site-packages/scipy/optimize/optimize.py:563: RuntimeWarning: invalid value encountered in subtract
  numpy.max(numpy.abs(fsim[0] - fsim[1:])) <= fatol):
/home/clayton/anaconda3/envs/wafo/lib/python3.6/site-packages/wafo/stats/estimation.py:41: UserWarning: Exceeded max iterations. (p_min0=[-6.57391905], p_min=[-1.38503693e-24], p=0.0)
  warnings.warn(msg)
/home/clayton/anaconda3/envs/wafo/lib/python3.6/site-packages/wafo/stats/estimation.py:41: UserWarning: Exceeded max iterations. (p_max0=[6.57391905], p_max=[1.38503693e-24], p=0.0)
  warnings.warn(msg)
/home/clayton/anaconda3/envs/wafo/lib/python3.6/site-packages/wafo/misc.py:856: RuntimeWarning: divide by zero encountered in true_divide
  (f[ind + 1] - f[ind]))
/home/clayton/anaconda3/envs/wafo/lib/python3.6/site-packages/wafo/misc.py:928: UserWarning: No level v = -944.77 crossings found in x
  warnings.warn('No level v = %0.5g crossings found in x' % v)
/home/clayton/anaconda3/envs/wafo/lib/python3.6/site-packages/wafo/stats/estimation.py:523: UserWarning: Number of crossings is zero, i.e., upper and lower bound is not found!
  warnings.warn('Number of crossings is zero, i.e., upper and lower '
/home/clayton/anaconda3/envs/wafo/lib/python3.6/site-packages/scipy/optimize/optimize.py:563: RuntimeWarning: invalid value encountered in subtract
  numpy.max(numpy.abs(fsim[0] - fsim[1:])) <= fatol):
/home/clayton/anaconda3/envs/wafo/lib/python3.6/site-packages/wafo/stats/estimation.py:365: UserWarning: The fitted parameters does not provide the optimum fit. Something wrong with fit (par = [-0.2352845   3.         -0.00389864], par_old= [-0.2352845   3.          2.91429383], dl = 1.1368683772161603e-13)
  dL))
/home/clayton/anaconda3/envs/wafo/lib/python3.6/site-packages/scipy/optimize/optimize.py:563: RuntimeWarning: invalid value encountered in subtract
  numpy.max(numpy.abs(fsim[0] - fsim[1:])) <= fatol):
/home/clayton/anaconda3/envs/wafo/lib/python3.6/site-packages/scipy/optimize/optimize.py:563: RuntimeWarning: invalid value encountered in subtract
  numpy.max(numpy.abs(fsim[0] - fsim[1:])) <= fatol):
/home/clayton/anaconda3/envs/wafo/lib/python3.6/site-packages/scipy/optimize/optimize.py:563: RuntimeWarning: invalid value encountered in subtract
  numpy.max(numpy.abs(fsim[0] - fsim[1:])) <= fatol):
/home/clayton/anaconda3/envs/wafo/lib/python3.6/site-packages/scipy/optimize/optimize.py:563: RuntimeWarning: invalid value encountered in subtract
  numpy.max(numpy.abs(fsim[0] - fsim[1:])) <= fatol):
/home/clayton/anaconda3/envs/wafo/lib/python3.6/site-packages/scipy/optimize/optimize.py:563: RuntimeWarning: invalid value encountered in subtract
  numpy.max(numpy.abs(fsim[0] - fsim[1:])) <= fatol):
/home/clayton/anaconda3/envs/wafo/lib/python3.6/site-packages/scipy/optimize/optimize.py:563: RuntimeWarning: invalid value encountered in subtract
  numpy.max(numpy.abs(fsim[0] - fsim[1:])) <= fatol):
/home/clayton/anaconda3/envs/wafo/lib/python3.6/site-packages/scipy/optimize/optimize.py:563: RuntimeWarning: invalid value encountered in subtract
  numpy.max(numpy.abs(fsim[0] - fsim[1:])) <= fatol):