title: Error when trying to create a Heatmap: '<=' not supported between instances of 'int' and 'str'
body: <p>I am trying to figure out the reason why I keep getting this error</p>
  <pre><code>pt_gov = gov.pivot_table(values=&quot;Income&quot;, columns=&quot;Year&quot;, index=&quot;State&quot;, aggfunc=&quot;sum&quot;)
  plt.figure(figsize=(32,20), dpi=150)
  
  ax = sns.heatmap(pt_gov, cmap=&quot;viridis_r&quot;, annot=True,
                  linewidths=0.005, linecolor=&quot;gray&quot;, fmt=&quot;,.0f&quot;,
                  cbar=True, annot_kws={&quot;size&quot;:15})
  ax.set_xticklabels([int(float(y.get_text())) for y in ax.get_xticklabels()])
  plt.ylabel(&quot;Income&quot;, size=20)
  plt.xlabel(&quot;Year&quot;, size=20)
  plt.show()
  </code></pre>
  <p>Error</p>
  <pre><code>---------------------------------------------------------------------------
  TypeError                                 Traceback (most recent call last)
  &lt;ipython-input-37-ab7b78c9421b&gt; in &lt;module&gt;
        3 plt.figure(figsize=(32,20), dpi=150)
        4 
  ----&gt; 5 ax = sns.heatmap(pt_fonden, cmap=&quot;viridis_r&quot;, annot=True,
        6                 linewidths=0.005, linecolor=&quot;gray&quot;, fmt=&quot;,.0f&quot;,
        7                 cbar=True, annot_kws={&quot;size&quot;:15})
  
  ~/opt/anaconda3/lib/python3.8/site-packages/seaborn/matrix.py in heatmap(data, vmin, vmax, cmap, center, robust, annot, fmt, annot_kws, linewidths, linecolor, cbar, cbar_kws, cbar_ax, square, xticklabels, yticklabels, mask, ax, **kwargs)
      533     &quot;&quot;&quot;
      534     # Initialize the plotter object
  --&gt; 535     plotter = _HeatMapper(data, vmin, vmax, cmap, center, robust, annot, fmt,
      536                           annot_kws, cbar, cbar_kws, xticklabels,
      537                           yticklabels, mask)
  
  ~/opt/anaconda3/lib/python3.8/site-packages/seaborn/matrix.py in __init__(self, data, vmin, vmax, cmap, center, robust, annot, fmt, annot_kws, cbar, cbar_kws, xticklabels, yticklabels, mask)
      162 
      163         # Determine good default values for the colormapping
  --&gt; 164         self._determine_cmap_params(plot_data, vmin, vmax,
      165                                     cmap, center, robust)
      166 
  
  ~/opt/anaconda3/lib/python3.8/site-packages/seaborn/matrix.py in _determine_cmap_params(self, plot_data, vmin, vmax, cmap, center, robust)
      201                 vmin = np.nanpercentile(calc_data, 2)
      202             else:
  --&gt; 203                 vmin = np.nanmin(calc_data)
      204         if vmax is None:
      205             if robust:
  
  &lt;__array_function__ internals&gt; in nanmin(*args, **kwargs)
  
  ~/opt/anaconda3/lib/python3.8/site-packages/numpy/lib/nanfunctions.py in nanmin(a, axis, out, keepdims)
      326         # Slow, but safe for subclasses of ndarray
      327         a, mask = _replace_nan(a, +np.inf)
  --&gt; 328         res = np.amin(a, axis=axis, out=out, **kwargs)
      329         if mask is None:
      330             return res
  
  &lt;__array_function__ internals&gt; in amin(*args, **kwargs)
  
  ~/opt/anaconda3/lib/python3.8/site-packages/numpy/core/fromnumeric.py in amin(a, axis, out, keepdims, initial, where)
     2790     6
     2791     &quot;&quot;&quot;
  -&gt; 2792     return _wrapreduction(a, np.minimum, 'min', axis, None, out,
     2793                           keepdims=keepdims, initial=initial, where=where)
     2794 
  
  ~/opt/anaconda3/lib/python3.8/site-packages/numpy/core/fromnumeric.py in _wrapreduction(obj, ufunc, method, axis, dtype, out, **kwargs)
       88                 return reduction(axis=axis, out=out, **passkwargs)
       89 
  ---&gt; 90     return ufunc.reduce(obj, axis, dtype, out, **passkwargs)
       91 
       92 
  
  TypeError: '&lt;=' not supported between instances of 'int' and 'str'
  
  &lt;Figure size 4800x3000 with 0 Axes&gt;
  </code></pre>
  <p>I am afraid I don't fully understand why this error is popping out, seems like it has sth to do with ax = sns.heatmap(pt_gov, cmap=&quot;viridis_r&quot;, annot=True,
  Could anybody please help me/explain?</p>
  <p>Thank you so much!</p>