docs: def prophist(self,prop,fig=None,log=False, mask=None,
                   selected=False,**kwargs):
          """Plots a 1-d histogram of desired property.
  
          :param prop:
              Name of property to plot.  Must be column of ``self.stars``.
  
          :param fig: (optional)
              Argument for :func:`plotutils.setfig`
  
          :param log: (optional)
              Whether to plot the histogram of log10 of the property.
  
          :param mask: (optional)
              Boolean array (length of ``self.stars``) to say
              which indices to plot (``True`` is good).
  
          :param selected: (optional)
              If ``True``, then only the "selected" stars (that is, stars
              obeying all distribution constraints attached to this object)
              will be plotted.  In this case, ``mask`` will be ignored.
  
          :param **kwargs:
              Additional keyword arguments passed to :func:`plt.hist`.
  
          """
  
          setfig(fig)
  
          inds = None
          if mask is not None:
              inds = np.where(mask)[0]
          elif inds is None:
              if selected:
                  #inds = np.arange(len(self.selected))
                  inds = self.selected.index
              else:
                  #inds = np.arange(len(self.stars))
                  inds = self.stars.index
  
          if selected:
              vals = self.selected[prop].values#.iloc[inds] #invalidates mask?
          else:
              vals = self.stars[prop].iloc[inds].values
  
          if prop=='depth' and hasattr(self,'depth'):
              vals *= self.dilution_factor[inds]
  
          if log:
              h = plt.hist(np.log10(vals),**kwargs)
          else:
              h = plt.hist(vals,**kwargs)
  
          plt.xlabel(prop)