class_docstr: Orthonormal (for weight=1) Chebychev Polynomial on (-1,1)
  
  
  Notes
  -----
  integration requires to stay away from boundary, offsetfactor > 0
  maybe this implies that we cannot use it for densities that are > 0 at
  boundary ???
  
  or maybe there is a mistake close to the boundary, sometimes integration works.
class_docstr_tok: ["Orthonormal","(","for","weight=1",")","Chebychev","Polynomial","on","(","-1,1",")","Notes","--","--","-","integration","requires","to","stay","away","from","boundary",",","offsetfactor",">","0","maybe","this","implies","that","we","can","not","use","it","for","densities","that","are",">","0","at","boundary","?","?","?","or","maybe","there","is","a","mistake","close","to","the","boundary",",","sometimes","integration","works","."]
code: def __init__(self, order):
      self.order = order
      from scipy.special import chebyt
  
      self.poly = chebyt(order)
      self.domain = (-1, 1)
      self.intdomain = (-1 + 1e-6, 1 - 1e-6)
      # not sure if I need this, in integration nans are possible  on the boundary
      self.offsetfactor = 0.01
  
imports: from scipy import stats, integrate, special
  import numpy
label_desc: Use image node_id 1 to create a new ChebyTPoly object  with example: obj = ChebyTPoly(order)