docs: def pathogenPanel(self, filename):
          """
          Make a panel of images, with each image being a graph giving pathogen
          de-duplicated (by id) read count (Y axis) versus sample id (X axis).
  
          @param filename: A C{str} file name to write the image to.
          """
          import matplotlib
          matplotlib.use('PDF')
          import matplotlib.pyplot as plt
  
          self._computeUniqueReadCounts()
          pathogenNames = sorted(self.pathogenNames)
          sampleNames = sorted(self.sampleNames)
  
          cols = 5
          rows = int(len(pathogenNames) / cols) + (
              0 if len(pathogenNames) % cols == 0 else 1)
          figure, ax = plt.subplots(rows, cols, squeeze=False)
  
          coords = dimensionalIterator((rows, cols))
  
          for i, pathogenName in enumerate(pathogenNames):
              row, col = next(coords)
              self._pathogenSamplePlot(pathogenName, sampleNames, ax[row][col])
  
          # Hide the final panel graphs (if any) that have no content. We do
          # this because the panel is a rectangular grid and some of the
          # plots at the end of the last row may be unused.
          for row, col in coords:
              ax[row][col].axis('off')
  
          figure.suptitle(
              ('Per-sample read count for %d pathogen%s and %d sample%s.\n\n'
               'Sample name%s: %s') % (
                   len(pathogenNames),
                   '' if len(pathogenNames) == 1 else 's',
                   len(sampleNames),
                   '' if len(sampleNames) == 1 else 's',
                   '' if len(sampleNames) == 1 else 's',
                   fill(', '.join(sampleNames), 50)),
              fontsize=20)
          figure.set_size_inches(5.0 * cols, 2.0 * rows, forward=True)
          plt.subplots_adjust(hspace=0.4)
  
          figure.savefig(filename)