def copy(self, other):
        Operator.copy(self, other)
Test function for DocumentNTF(): check plot with f0 = 0.333 2/3
dataset/ETHPy150Open uwescience/raco/raco/algebra.py/ZeroaryOperator.copy--crossover with--dataset/ETHPy150Open ggventurini/python-deltasigma/deltasigma/tests/test_DocumentNTF.py/TestDocumentNTF.test_documentNTF2