Problem with function call in example plot_UOT_barycenter_1D.py

[KonradStreit]

When running the example plot_UOT_barycenter_1D.py the weights get passed into unbalanced.py but are interpreted as the method. Therefore an error comes up:

Traceback (most recent call last):

  File "<ipython-input-56-90bb6b274118>", line 1, in <module>
    runfile('.../plot_UOT_barycenter_1D(1).py', wdir='C:/Users/kvstr/Downloads')

  File "...\Anaconda3\envs\my_env\lib\site-packages\spyder_kernels\customize\spydercustomize.py", line 827, in runfile
    execfile(filename, namespace)

  File "...\Anaconda3\envs\my_env\lib\site-packages\spyder_kernels\customize\spydercustomize.py", line 110, in execfile
    exec(compile(f.read(), filename, 'exec'), namespace)

  File ".../plot_UOT_barycenter_1D(1).py", line 80, in <module>
    bary_wass = ot.unbalanced.barycenter_unbalanced(A, M, reg, alpha, weights)

  File "...\Anaconda3\envs\my_env\lib\site-packages\ot\unbalanced.py", line 1003, in barycenter_unbalanced
    if method.lower() == 'sinkhorn':

AttributeError: 'numpy.ndarray' object has no attribute 'lower'

I have tested on multiple machines with clean python installations, mainly on Windows 10 64-bit, but could also be reproduced on a Linux machine.

Windows-10-10.0.18362-SP0, although also reproduced on Linux
Python 3.7.6 (default, Jan 8 2020, 20:23:39) [MSC v.1916 64 bit (AMD64)], also tested in a 3.6 Anaconda environment with same result
NumPy 1.18.1
SciPy 1.4.1
POT 0.6.0

By just downloading and running the example file from readthedocs it should be reproducable.

As far as I can tell, changing the function calls in lines 80 and 114 from

ot.unbalanced.barycenter_unbalanced(A, M, reg, alpha, weights)

to

ot.unbalanced.barycenter_unbalanced(A, M, reg, alpha, weights=weights)

fixes this issue. There is a seperate issue I found with the unbalanced.barycenter_unbalanced funtion that still keeps the example from working which I will raise seperately.

[rflamary]

This has been corrected in PR #143