Source code for slugpy.cloudy.read_cloudy_linelist

"""
Routine to read a cloudy line list output, produced by save last line list
"""

import numpy as np
from collections import namedtuple



def read_cloudy_linelist(filename):
    """
    Reads a cloudy line list output, produced by save last line list

    Parameters
       filename : string
          name of the file to be read

    Returns
       A namedtuple containing the following fields:

       labels : array, dtype 'S4'
          list of line labels
       wl : array
          array of line wavelengths, in Angstrom
       lum : array
          array of line luminosities; this will be in whatever units the
          cloudy output is in
    """

    # Open file
    fp = open(filename, 'r')

    # Burn header lines
    fp.readline()
    fp.readline()

    # Read data
    labels=[]
    wl=[]
    lum=[]
    for line in fp:

        # Skip blank lines and lines that start with hash marks, which
        # are comments
        if len(line.strip()) == 0:
            continue
        if line.strip()[0] == '#':
            continue

        # First 4 characters are descriptor
        labels.append(line[:4])

        # Characters from 5 to tab are wavelength; last character is unit;
        # handle special case of exactly 0 wavelength, which occurs for
        # reasons only Gary can fathom...
        wlstr = line[5:].split('\t')[0].strip()
        if (wlstr == '0'):
            labels = labels[:-1]
            continue
        wlnum = wlstr[:-1]
        wlunit = wlstr[-1]
        if wlunit == 'A':
            multiplier = 1.0
        elif wlunit == 'm':
            multiplier = 1e4
        else:
            raise ValueError("unknown unit in line "+line)
        wl.append(float(wlnum)*multiplier)

        # Quantity after tab is luminosity
        linesplit=line.split('\t')
        lum.append(float(linesplit[1]))

    # Close file
    fp.close()

    # Convert to arrays
    labels = np.array(labels)
    wl = np.array(wl)
    lum = np.array(lum)

    # Return
    out_type = namedtuple('cloudy_linelist', ['label', 'wl', 'lum'])
    return out_type(labels, wl, lum)