#--- shell  (Ubuntu 17.10, Octave 4.2.1, Python 3.6.4)
pip install oct2py==4.0.6

#--- Python
x=[0.,0,0,0,0,1,1,1,1,0,0,0,0,0]

from oct2py import Oct2Py
with Oct2Py() as oc:
    oc.eval('pkg load signal')
    y = oc.sgolayfilt(x,3,5)

#--- stderr
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "~/miniconda3/lib/python3.6/site-packages/oct2py/dynamic.py", line 96, in __call__
    return self._ref().feval(self.name, *inputs, **kwargs)
  File "~/miniconda3/lib/python3.6/site-packages/oct2py/core.py", line 369, in feval
    store_as=store_as, plot_dir=plot_dir)
  File "~/miniconda3/lib/python3.6/site-packages/oct2py/core.py", line 568, in _feval
    raise Oct2PyError(msg)
oct2py.utils.Oct2PyError: Octave evaluation error:
error: =: nonconformant arguments (op1 is 1x5, op2 is 3x5)


#--- work in plain Octave 4.2.1
x=[0.,0,0,0,0,1,1,1,1,0,0,0,0,0];
pkg load signal
y = sgolayfilt(x,3,5);

type y
y is a variable
 Columns 1 through 5:

   0.00000   0.00000   0.00000  -0.08571   0.25714

 Columns 6 through 10:

   0.74286   1.08571   1.08571   0.74286   0.25714

 Columns 11 through 14:

  -0.08571   0.00000   0.00000   0.00000

# --- omitting all but first argument works from Python
sgolayfilt(x) == sgolayfilt(x,3,5) since those are the default parameters.

y = oc.sgolayfilt(x)
>>> y
array([[ 0.        ,  0.        ,  0.        , -0.08571429,  0.25714286,
         0.74285714,  1.08571429,  1.08571429,  0.74285714,  0.25714286,
        -0.08571429,  0.        ,  0.        ,  0.        ]])