title: Seaborn tsplot not showing data
body: <p>I'm trying to use seaborn to make a simple tsplot, but for reasons that aren't clear to me nothing shows up when I run the code. Here's a minimal example:</p>
  
  <pre><code>import numpy as np
  import seaborn as sns
  import pandas as pd
  
  df = pd.DataFrame({'value': np.random.rand(31), 'time': range(31)})
  
  ax = sns.tsplot(data=df, value='value', time='time')
  sns.plt.show()
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/2zdwP.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/2zdwP.png" alt="enter image description here"></a></p>
  
  <p>Usually tsplot you supply multiple data points for each time point, but does it just not work if you only supply one?</p>
  
  <p>I know matplotlib can be used to do this pretty easily, but I wanted to use seaborn for some of its other functionality. </p>