class_docstr: class to hold quadratic function with inverse function and derivative
  
  using instance methods instead of class methods, if we want extension
  to parametrized function
class_docstr_tok: ["class","to","hold","quadratic","function","with","inverse","function","and","derivative","using","instance","methods","instead","of","class","methods",",","if","we","want","extension","to","parametrized","function"]
code: def inverseminus(self, x):
      return 0.0 - np.sqrt(x)
  
imports: from scipy import stats
  from scipy.stats import distributions
  import numpy
label_desc: Use image node_id 2 for calling the SquareFunc obj's underlying member method code with example usage: obj.inverseminus(x) and returns: unknown