old_contents: import os
  import glob
  
  from astropy import units as u
  
  from sedfitter import (fit, plot, plot_params_1d, plot_params_2d,
                         write_parameters, write_parameter_ranges)
  from sedfitter.extinction import Extinction
  
  # Define path to models
  model_dir = '/Volumes/Data/models/models_r06'
  
  # Read in extinction law)
  extinction = Extinction.from_file('kmh94.par', columns=[0, 3],
                                    wav_unit=u.micron, chi_unit=u.cm**2 / u.g)
  
  # Define filters and apertures
  filters = ['2J', '2H', '2K', 'I1', 'I2', 'I3', 'I4']
  apertures = [3., 3., 3., 3., 3., 3., 3.] * u.arcsec
  
  # Run the fitting
  fit('data_glimpse', filters, apertures, model_dir,
      'output.fitinfo',
      extinction_law=extinction,
      distance_range=[1., 2.] * u.kpc,
      av_range=[0., 40.])
  
  # For the remaining commands, we always select the models with chi^2-chi_best^2
  # per datapoint less than 3.
  select_format = ('F', 3)
  
  # Make SED plots
  plot('output.fitinfo', 'plots_seds', plot_max=100, select_format=select_format)
  
  # Make histograms of the disk mass
  plot_params_1d('output.fitinfo', 'MDISK', 'plots_mdisk',
                 log_x=True, select_format=select_format)
  
  # Make 2-d plots of the envelope infall rate vs disk mass
  plot_params_2d('output.fitinfo', 'MDISK', 'MDOT', 'plots_mdot_mdisk',
                 log_x=True, log_y=True, select_format=select_format)
  
  # Write out all models with a delta chi^2-chi_best^2 per datapoint < 3
  write_parameters('output.fitinfo', 'parameters.txt',
                   select_format=select_format)
  
  # Write out the min/max ranges corresponding to the above file
  write_parameter_ranges('output.fitinfo', 'parameter_ranges.txt',
                         select_format=select_format)
new_contents: import os
  import glob
  
  from astropy import units as u
  
  from sedfitter import (fit, plot, plot_params_1d, plot_params_2d,
                         write_parameters, write_parameter_ranges)
  from sedfitter.extinction import Extinction
  
  # Define path to models
  model_dir = '/Volumes/Data/models/models_r06'
  
  # Read in extinction law. We read in columns 1 (the wavelength in microns) and
  # 4 (the opacity in cm^2/g)
  extinction = Extinction.from_file('kmh94.par', columns=[0, 3],
                                    wav_unit=u.micron, chi_unit=u.cm**2 / u.g)
  
  # Define filters and apertures
  filters = ['2J', '2H', '2K', 'I1', 'I2', 'I3', 'I4']
  apertures = [3., 3., 3., 3., 3., 3., 3.] * u.arcsec
  
  # Run the fitting
  fit('data_glimpse', filters, apertures, model_dir,
      'output.fitinfo',
      extinction_law=extinction,
      distance_range=[1., 2.] * u.kpc,
      av_range=[0., 40.])
  
  # For the remaining commands, we always select the models with chi^2-chi_best^2
  # per datapoint less than 3.
  select_format = ('F', 3)
  
  # Make SED plots
  plot('output.fitinfo', 'plots_seds', plot_max=100, select_format=select_format)
  
  # Make histograms of the disk mass
  plot_params_1d('output.fitinfo', 'MDISK', 'plots_mdisk',
                 log_x=True, select_format=select_format)
  
  # Make 2-d plots of the envelope infall rate vs disk mass
  plot_params_2d('output.fitinfo', 'MDISK', 'MDOT', 'plots_mdot_mdisk',
                 log_x=True, log_y=True, select_format=select_format)
  
  # Write out all models with a delta chi^2-chi_best^2 per datapoint < 3
  write_parameters('output.fitinfo', 'parameters.txt',
                   select_format=select_format)
  
  # Write out the min/max ranges corresponding to the above file
  write_parameter_ranges('output.fitinfo', 'parameter_ranges.txt',
                         select_format=select_format)
subject: Clarify use of extinction law