class_docstr: Gumbel copula.
  
  Dependence is greater in the positive tail than in the negative.
  
  .. math::
  
      C_\theta(u,v) = \exp\!\left[ -\left( (-\log(u))^\theta +
      (-\log(v))^\theta \right)^{1/\theta} \right]
  
  with :math:`\theta\in[1,\infty)`.
class_docstr_tok: ["Gumbel","copula",".","Dependence","is","greater","in","the","positive","tail","than","in","the","negative",".","..","math",":",":","C_\\theta","(","u",",","v",")","=","\\exp\\","!","\\left","[","-\\left","(","(","-\\log","(","u",")",")","^\\theta","+","(","-\\log","(","v",")",")","^\\theta","\\right",")","^","{","1\/\\theta","}","\\right","]","with",":","math",":","`","\\theta\\in","[","1",",","\\infty",")","`","."]
code: def __init__(self, theta=None, k_dim=2):
      if theta is not None:
          args = (theta,)
      else:
          args = ()
      super().__init__(
          transforms.TransfGumbel(), args=args, k_dim=k_dim
      )
  
      if theta is not None:
          if theta <= 1:
              raise ValueError("Theta must be > 1")
      self.theta = theta
  
imports: import sys
  import numpy
  from scipy import stats, integrate, optimize
  from .None import transforms
  from .copulas import Copula
  from statsmodels.tools.rng_qrng import check_random_state
label_desc: Use image node_id 1 to create a new GumbelCopula object from inherited base classes: ArchimedeanCopula with example: obj = GumbelCopula(theta, k_dim)