code: def prop_triangle(self, **kwargs):
          
          truths = []
          params = []
          for p in self.properties:
              try:
                  val, err = self.properties[p]
              except:
                  continue
  
              if p in self.ic.bands:
                  params.append('{}_mag'.format(p))
                  truths.append(val)
              elif p=='parallax':
                  params.append('distance')
                  truths.append(1/(val/1000.))
              else:
                  params.append(p)
                  truths.append(val)
          return self.triangle(params, truths=truths, **kwargs)
docs: Makes corner plot of only observable properties.
  
          The idea here is to compare the predictions of the samples
          with the actual observed data---this can be a quick way to check
          if there are outlier properties that aren't predicted well
          by the model.
  
          :param **kwargs:
              Keyword arguments passed to :func:`StarModel.triangle`.
  
          :return:
              Figure object containing corner plot.