title: Pandas groupby scatter plot in a single plot
body: <p>This is a followup question on this <a href="https://stackoverflow.com/a/42988389/6347629">solution</a>. There is automatic assignment of different colors when <code>kind=line</code> but for scatter plot that's not the case.</p>
  <pre><code>import pandas as pd
  import matplotlib.pylab as plt
  import numpy as np
  
  # random df
  df = pd.DataFrame(np.random.randint(0,10,size=(25, 3)), columns=['label','x','y'])
  
  # plot groupby results on the same canvas 
  fig, ax = plt.subplots(figsize=(8,6))
  df.groupby('label').plot(kind='scatter', x = &quot;x&quot;, y = &quot;y&quot;, ax=ax)
  </code></pre>
  <p><a href="https://i.stack.imgur.com/i7b6S.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/i7b6S.png" alt="enter image description here" /></a></p>
  <p>There is a connected issue <a href="https://github.com/pandas-dev/pandas/issues/21963" rel="nofollow noreferrer">here</a>. Is there any simple workaround for this?</p>
  <p><strong>Update:</strong></p>
  <p>When I try the solution recommended by @ImportanceOfBeingErnest for a <code>label</code> column with strings, its not working!</p>
  <pre><code>df = pd.DataFrame(np.random.randint(0,10,size=(5, 2)), columns=['x','y'])
  df['label'] = ['yes','no','yes','yes','no']
  fig, ax = plt.subplots(figsize=(8,6))
  ax.scatter(x='x', y='y', c='label', data=df) 
  </code></pre>
  <p>It throws following error,</p>
  <blockquote>
  <p>ValueError: Invalid RGBA argument: 'yes'</p>
  <p>During handling of the above exception, another exception occurred:</p>
  </blockquote>