title: Input Format to pcolormesh
body: <p>I'm attempting to make heat/intensity map using Basemap. My inputs are a set of lats, lons, and intensity at that point. The dataset looks like this:</p>
  
  <pre><code>lat[0], lon[0] = intensity[0]
  lat[1], lon[1] = intensity[1]
  ...
  lat[n], lon[n] = intensity[n]
  </code></pre>
  
  <p>At each index the lat and lon correspond to the correct sensor reading. My code looks something like this:</p>
  
  <pre><code>fig = plt.figure(figsize=(10, 8))
  
  
  # Set title
  fig.suptitle("Intensities {} {}".format(start_time, stop_time))
  
  
  # US Centered Map
  map_axis = fig.add_subplot(111)
  map = Basemap(
      ax = map_axis,
      lat_0 = 40, lon_0 = -95,
      width = 6500e3, height = 6500e3,
      projection = 'stere',
      resolution = 'l'
  )
  map.drawcoastlines()
  
  
  lats = ...
  lons = ...
  intn = ...
  
  
  # Convert coordinates
  lons, lats = map(lons, lats)
  
  
  LONS, LATS = np.meshgrid(lons, lats)
  map.pcolormesh(
      LONS, LATS,
      intn,
      vmin = 0, vmax = 100
  )
  
  
  fig.savefig(file_name)
  plt.close(fig) 
  </code></pre>
  
  <p>This code never completes. I've successfully plotted the Basemap by itself. The pcolormesh is what is failing. The program crashes with this error.</p>
  
  <pre><code>    $ ./plot_intensities.py
      Running 2013-04-10 00:02:30 2013-04-10 00:02:45
      Traceback (most recent call last):
        File "./plot_intensities.py", line 151, in &lt;module&gt;
          make_maps(samples)
        File "./plot_intensities.py", line 144, in make_maps
          make_map(bin_samples, start, walk)
        File "./plot_intensities.py", line 117, in make_map
          vmin = 0, vmax = 100
        File "/usr/lib/python3/dist-packages/mpl_toolkits/basemap/__init__.py", line 521, in with_transform
          return plotfunc(self,x,y,data,*args,**kwargs)
        File "/usr/lib/python3/dist-packages/mpl_toolkits/basemap/__init__.py", line 3418, in pcolormesh
          ret =  ax.pcolormesh(x,y,data,**kwargs)
        File "/usr/lib/python3/dist-packages/matplotlib/__init__.py", line 1814, in inner
          return func(ax, *args, **kwargs)
        File "/usr/lib/python3/dist-packages/matplotlib/axes/_axes.py", line 5395, in pcolormesh
          X, Y, C = self._pcolorargs('pcolormesh', *args, allmatch=allmatch)
        File "/usr/lib/python3/dist-packages/matplotlib/axes/_axes.py", line 4995, in _pcolorargs
          numRows, numCols = C.shape
      ValueError: not enough values to unpack (expected 2, got 1)
  </code></pre>
  
  <p>I understand that my data, the third argument <code>intn</code> is not formatted correctly. I cannot find any documentation as to how I should shape that list. How do I format it to the correct shape? </p>
  
  <p>Thanks.</p>