combine

#!/usr/bin/env python

import sys
import os
from rootpy.extern.argparse import ArgumentParser

parser = ArgumentParser()
parser.add_argument('--name', default='combined')
parser.add_argument('--verbose', action='store_true', default=False)
parser.add_argument('--path', default=None)
parser.add_argument('files', nargs='+')
args = parser.parse_args()

root_file = '{0}.root'.format(args.name)
xml_path = args.name

if args.path is not None:
    root_file = os.path.join(args.path, root_file)
    xml_path = os.path.join(args.path, xml_path)

if os.path.exists(root_file):
    sys.exit("output ROOT file already exists: {0}".format(root_file))
    
if os.path.exists(xml_path):
    sys.exit("XML output directory already exists: {0}".format(xml_path))

from rootpy.stats.histfactory import (
    measurements_from_xml, write_measurement,
    make_measurement)
from statstools.fixups import find_measurements

# get measurements
measurements = []
for file in args.files:
    # if file is a directory then find all measurement XMLs under it
    if os.path.isdir(file):
        meas = []
        for dirpath, meas_file in find_measurements(file):
            path = os.path.join(dirpath, meas_file)
            meas.extend(measurements_from_xml(
                path,
                cd_parent=True,
                collect_histograms=True,
                silence=not args.verbose))
    else:
        meas = measurements_from_xml(
            file,
            cd_parent=True,
            collect_histograms=True,
            silence=not args.verbose)
    if not meas:
        sys.exit("No measurements in {0}".format(file))
    measurements.extend(meas)

# combine all channels into a new measurement
channels = []
channel_names = {}
for meas in measurements:
    for channel in meas.channels:
        if channel.name in channel_names:
            # ignore duplicate channels
            continue
        channels.append(channel)
        channel_names[channel.name] = None

# use settings from the first measurement
# (POI and constant params)
combined_measurement = make_measurement(
    args.name, channels,
    POI=measurements[0].poi,
    const_params=measurements[0].const_params)

# write out the new measurement and workspace
write_measurement(
    combined_measurement,
    root_file=root_file,
    xml_path=xml_path,
    write_workspaces=True,
    silence=not args.verbose)