title: Prob using axes for subplot an get AttributeError: 'numpy.ndarray' object has no attribute 'plot'
body: <p>'''<br />
  matplotlib.use(&quot;Qt5Agg&quot;)</p>
  <pre><code>pas = [1,2,3,4,5,6,7,8,9,10]
  
  # set up l'organisation de la figure
  fig, axs = plt.subplots(nrows=3,ncols=len(pas))
  
  
  manager = plt.get_current_fig_manager()
  manager.window.showMaximized()
  plt.show()
       
  axs[1, 0+1].set(ylabel='fréquence (set test)')
  for iii in range(0, len(pas)):
      
      bins = np.linspace(round(y[:,iii].min()), round(y[:,iii].max()), 20)
      axs[0, iii].hist(yhat_graph[:,iii], bins, color = 'steelblue', alpha = 0.5, label='simulation')
      axs[0, iii].hist(y[:,iii], bins, color = 'orange', alpha=0.5, label='ref. apport hist.')
      axs[0, iii].set(xlabel='apports m3/sec')
  
      axs[0, iii].legend(loc='upper right')
      axs[0, iii].set(title='prévision J+'  + str(iii+1) + ' (set test)' )
      
  
  axs[1, 0].set(ylabel='Variations journalières Jn - Jn-1 (set test) \n observation')
  for iii in range(0, len(pas)-1):
      axs[1, iii].plot()
      graph_scatter(ecart_valid_y[iii],
                    ecart_yhat[iii], True,'simulation','','var. j' + str(iii+1) +' - j ' + str(iii) ,'steelblue')
      axs[1, iii].set(xlabel='simulation')
  
  
  if history == 'missing':
      print('pas de fichier history')
      axs[2,0:].plot()
  else:
      axs[2, 0].plot()
      graph_loss(history)
      axs[2,1:].plot()
  
  graph_sim_multiStep(y[-windowGraph[0]:-windowGraph[1]], yhat_graph[-windowGraph[0]:-windowGraph[1]], nash, kge, titre)
  </code></pre>
  <p>'''</p>
  <p>with this line &quot;axs[2,1:].plot()&quot;</p>
  <p>I've got this error:
  AttributeError: 'numpy.ndarray' object has no attribute 'plot'</p>
  <p>the function 'graph_loss' and 'graph_scatter' work fine lonely</p>