initial commit of Python3 port

CHANGELOG.txt

+Version 0.4.0
+	general:
+		port to python3
+
+Version 0.3.1
+	general:
+		Disable by default datacenter
+	plot:
+		Change default plot size
+		Use tight_layout
+		Improve detection of AM/PM dates
+		Allow to plot only the 2nd plot (NSB vs datetime)
+		plot.py now works also as a standalone tool (with user provided data file path).
+
+
+Version 0.3.0
+	general:
+	    Added datacenter support
+
+
+Version 0.2.2
+	general:
+		Adopt v1.0 of the standard format
+		 (including the filename for the daily data and plots)
+	read:
+		put the rx,cx and ix data in the header
+	plot:
+		Change de Serial number label		
+		
+
+Version 0.2.1
+	read:
+		Print the errors in make_plot call on screen.
+	plot:
+		Only print the PM/AM/Moon labels on one panel.
+		Print the SQM serial number.
+
+Version 0.2.0
+	general:
+		Deep changes to make the program more modular.
+		The program now can be packaged as a single .exe file with PyInstaller.
+		The program can also be packaged for Linux systems.
+	read:
+		Try to use the fixed device address before looking for it automatically
+		 this should allow the use of multiple devices in a single computer.
+	plot:
+		Code cleanup.
+		Use local date/time in plots.
+		Write statistics file.
+		Use pyephem to calculate the moon phase (more accurate).
+		Show the Moon max altitude (transit altitude or culmination).
+		Plot the astronomical twilights.
+		Object Oriented programming.
+	email:
+		Now the program can be distributed without email module.
+
+Version 0.1.X
+	read:
+		Variables moved to config file.
+		Clean-up of the code.
+		Improve device reset.
+		New read software. OO programing.
+	plot:
+		Variables moved to config file.
+		Renamed from plot_sqmle.py to pysqm_plot.py
+		Make the code and linebreaks less ugly
+		Fixed axis.
+		Moon phase plot.
+	email:
+		Renamed from email_sqmle.py to pysqm_email.py  
+
+Version 0.0.X
+	First version.

MANIFEST.in

+include LICENSE.txt

README.txt

+PySQM
+=====
+
+PySQM is a multi-platform, open-source software designed to read and
+plot data from Unihedron SQM-LE and SQM-LU photometers, giving as 
+an output files with the 'International Dark Sky Association (IDA) 
+NSBM Community Standards for Reporting Skyglow Observations' format
+(http://www.darksky.org/night-sky-conservation/248).
+
+PySQM is distributed under GNU GPL, either version 3 of the License, 
+or (at your option) any later version. See the file LICENSE.txt for details.
+
+This software has been developed by Mireia Nievas <mnievas@ucm.es> with
+the invaluable help of:
+
+ - Sergio Pascual (UCM)
+ - Jaime Zamorano (UCM)
+ - Laura Barbas (OAN)
+ - Pablo de Vicente (OAN)
+
+The initial port to Python3 has been done by Anthony Tekatch (Unihedron).
+
+SETUP
+=====
+
+After downloading the software, you need to modify the file config.py. 
+In this file you will find several variables that need to be configured
+to match your hardware settings. For example:
+
+ - Location of the observatory (geographical coordinates).
+ - Device identifier.
+ - Device address (either IP address for SQM-LE or COM/ttyUSB port).
+ - Location of the data files.
+ - Axis limits for the plot.
+
+Remember that python (2.7) syntax is mandatory in this file
+
+
+HOW TO USE THE SOFTWARE
+=======================
+
+After configuring the software, make sure you are in the parent directory were
+the README, LICENSE and MANIFEST files are located
+> ls 
+LICENSE.txt  MANIFEST.in  README.txt  pysqm  config.py  setup.py
+
+And then run the software.
+> python -m pysqm 
+
+The program should find your SQM device and the data adquisition.will start 
+(if it's night-time). 
+
+In some systems, where python3 is the default version of python, you need 
+to specify python2 as the interpreter to use. This is done usually running 
+it as:
+
+> python2 -m pysqm
+
+or
+
+> python2.7 -m pysqm
+
+Note: running the setup.py script is neither tested nor required.
+The program is currently being redesigned as a normal python package, but at 
+present no setup is required.
+
+
+HOW IT WORKS
+============
+
+In a first step, the program tries to connect to the SQM photometer and takes
+some 'tests' measures (metadata/information, calibration and data) to check 
+that the device is working as expected. 
+
+After that, the program begins data acdquisition. In each iteration, it checks 
+whether it is night-time. In that case new data is taken. 
+
+Each N measurements, the main program calls a plotting function to generate 
+a graphical representation of the current nightly data.
+
+
+PySQM known issues
+==================
+
+Non-ASCII characters are not supported in the config.py file. Please, avoid using 'ñ', accented vowels, etc.
+In headless systems, such as the Raspberry PI, if you run the program without X, you may suffer from the following fatal error when the program tries to generate the plot:
+
+This application failed to start because it could not find or load the Qt platform plugin “xcb”.
+Available platform plugins are: eglfs, kms, linuxfb, minimal, minimalegl, offscreen, xcb.
+Reinstalling the application may fix this problem.  Aborted (core dumped)
+
+In order to avoid this problem, you need to create (or modify if the file exists) in your HOME directory the following file: 
+
+.config/matplotlib/matplotlibrc
+
+You just need to set the matplotlib backend to Agg:
+backend : Agg
+
+Save the changes and exit. Now, PySQM should make the plots without issues. You may need to restart PySQM to apply the changes.
+
+Path to EXE files (windows only):
+https://www.dropbox.com/s/xlbr6ktk8spjsse/PySQM.exe?dl=0
+
+CHANGELOG
+=========
+
+v0.3:
+    Added datacenter option (optional, disabled by default)
+
+v0.2:
+    ...
+
+v0.1:
+    ...
+

config.py

+#!/usr/bin/env python
+
+'''
+PySQM configuration File.
+____________________________
+
+Copyright (c) Mireia Nievas <mnievas[at]ucm[dot]es>
+
+This file is part of PySQM.
+
+PySQM is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+PySQM is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with PySQM.  If not, see <http://www.gnu.org/licenses/>.
+
+____________________________
+Notes:
+
+You may need to change the following variables to match your
+observatory coordinates, instrumental properties, etc.
+
+Python syntax is mandatory.
+____________________________
+'''
+
+
+'''
+-------------
+SITE location
+-------------
+'''
+
+_observatory_name = 'GURUGU'
+_observatory_latitude  = 40.447862
+_observatory_longitude = -3.364992
+_observatory_altitude  = 680
+_observatory_horizon   = 10     # If Sun is below this altitude, the program will take data
+
+_device_shorttype = 'SQM' # Device STR in the file
+_device_type = 'SQM_LU'   # Device type in the Header
+_device_id = _device_type + '-' + _observatory_name # Long Device lame
+_device_locationname = 'Villalbilla/Spain - Observatorio GURUGU'         # Device location in the world
+_data_supplier = 'Mireia Nievas / Universidad Complutense de Madrid'  # Data supplier (contact)
+_device_addr = '/dev/ttyUSB1'  # Default IP address of the ethernet device (if not automatically found)
+_measures_to_promediate = 1       # Take the mean of N measures
+_delay_between_measures = 2    # Delay between two measures. In seconds.
+_cache_measures = 1             # Get X measures before writing on screen/file
+_plot_each = 1                 # Call the plot function each X measures.
+
+_use_mysql = False        # Set to True if you want to store data on a MySQL db.
+_mysql_host = None        # Host (ip:port / localhost) of the MySQL engine.
+_mysql_user = None        # User with write permission on the db.
+_mysql_pass = None        # Password for that user.
+_mysql_database = None    # Name of the database.
+_mysql_dbtable = None     # Name of the table
+_mysql_port = None        # Port of the MySQL server.
+
+_local_timezone     = +1     # UTC+1
+_computer_timezone  = +0     # UTC
+_offset_calibration = -0.11  # magnitude = read_magnitude + offset
+_reboot_on_connlost = False  # Reboot if we loose connection
+
+# Monthly (permanent) data
+monthly_data_directory = "/tmp/sqm_gurugu/"
+# Daily (permanent) data
+daily_data_directory = monthly_data_directory+"/datos_diarios/"
+limits_nsb = [20.0,16.5] # Limits in Y-axis
+
+# Daily (permanent) graph
+daily_graph_directory = monthly_data_directory+"/graficos_diarios/"
+# Current data, deleted each day.
+current_data_directory = monthly_data_directory
+# Current graph, deleted each day.
+current_graph_directory = monthly_data_directory
+# Summary with statistics for the night
+summary_data_directory = monthly_data_directory
+
+
+'''
+----------------------------
+PySQM data center (OPTIONAL)
+----------------------------
+'''
+
+# Send the data to the data center
+_send_to_datacenter = False
+
+
+'''
+Ploting options
+'''
+full_plot = True
+limits_nsb = [20.0,16.5] # Limits in Y-axis
+limits_time   = [17,9] # Hours
+limits_sunalt = [-80,5] # Degrees
+
+'''
+Email options
+'''
+_send_data_by_email = False
+

pysqm/__init__.py

+#!/usr/bin/env python
+
+'''
+PySQM __init__ code
+____________________________
+
+Copyright (c) Mireia Nievas <mnievas[at]ucm[dot]es>
+
+This file is part of PySQM.
+
+PySQM is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+PySQM is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with PySQM.  If not, see <http://www.gnu.org/licenses/>.
+'''
+
+__author__ = "Mireia Nievas"
+__copyright__ = "Copyright (c) 2014 Mireia Nievas"
+__credits__ = [\
+ "Mireia Nievas @ UCM",\
+ "Jaime Zamorano @ UCM",\
+ "Laura Barbas @ OAN",\
+ "Pablo de Vicente @ OAN"\
+ "Anthony Tekatch @ Unihedron "\
+ ]
+__license__ = "GNU GPL v3"
+__shortname__ = "PySQM"
+__longname__ = "Python Sky Quality Meter pipeline"
+__version__ = "0.4.0"
+__maintainer__ = "Thorsten Alteholz"
+__email__ = "python[at]alteholz[dot]de"
+__status__ = "Development" # "Prototype", "Development", or "Production"
+
+from types import ModuleType
+import sys
+

pysqm/__main__.py

+#!/usr/bin/env python
+
+'''
+PySQM __main__ code
+____________________________
+
+Copyright (c) Mireia Nievas <mnievas[at]ucm[dot]es>
+
+This file is part of PySQM.
+
+PySQM is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+PySQM is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with PySQM.  If not, see <http://www.gnu.org/licenses/>.
+____________________________
+'''
+
+#from types import ModuleType
+#import sys
+
+import pysqm.main as main
+
+while(1==1):
+    # Loop forever to make sure the program does not die.
+    try:
+        main.loop()
+    except Exception as e:
+        print('')
+        print('FATAL ERROR while running the main loop !!')
+        print('Error was:')
+        print(e)
+        print('Trying to restart')
+        print('')
+

pysqm/common.py

+#!/usr/bin/env python
+
+'''
+PySQM common code
+____________________________
+
+Copyright (c) Mireia Nievas <mnievas[at]ucm[dot]es>
+
+This file is part of PySQM.
+
+PySQM is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+PySQM is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with PySQM.  If not, see <http://www.gnu.org/licenses/>.
+____________________________
+'''
+
+import math
+import ephem
+import datetime
+
+# Read the config variables from config.py
+import pysqm.settings as settings
+config = settings.GlobalConfig.config
+
+def define_ephem_observatory():
+    ''' Define the Observatory in Pyephem '''
+    OBS = ephem.Observer()
+    OBS.lat = config._observatory_latitude*ephem.pi/180
+    OBS.lon = config._observatory_longitude*ephem.pi/180
+    OBS.elev = config._observatory_altitude
+    return(OBS)
+
+def remove_linebreaks(data):
+    # Remove line breaks from data
+    data = data.replace('\r\n','')
+    data = data.replace('\r','')
+    data = data.replace('\n','')
+    return(data)
+
+def format_value(data,remove_str=' '):
+    # Remove string and spaces from data
+    data = remove_linebreaks(data)
+    data = data.replace(remove_str,'')
+    data = data.replace(' ','')
+    return(data)
+
+def format_value_list(data,remove_str=' '):
+    # Remove string and spaces from data array/list
+    data = [format_value(line,remove_str).split(';') for line in data]
+    return(data)
+
+def set_decimals(number,dec=3):
+        str_number = str(number)
+        int_,dec_ = str_number.split('.')
+        while len(dec_)<=dec:
+            dec_=dec_+'0'
+
+        return(int_+'.'+dec_[:dec])
+
+class observatory(object):
+    def read_datetime(self):
+        # Get UTC datetime from the computer.
+        utc_dt = datetime.datetime.utcnow()
+        #utc_dt = datetime.datetime.now() - datetime.timedelta(hours=config._computer_timezone)
+                #time.localtime(); daylight_saving=_.tm_isdst>0
+        return(utc_dt)
+
+    def local_datetime(self,utc_dt):
+        # Get Local datetime from the computer, without daylight saving.
+        return(utc_dt + datetime.timedelta(hours=config._local_timezone))
+
+    def calculate_sun_altitude(self,OBS,timeutc):
+        # Calculate Sun altitude
+        OBS.date = ephem.date(timeutc)
+        Sun = ephem.Sun(OBS)
+        return(Sun.alt)
+
+    def next_sunset(self,OBS):
+        # Next sunset calculation
+        previous_horizon = OBS.horizon
+        OBS.horizon = str(config._observatory_horizon)
+        next_setting = OBS.next_setting(ephem.Sun()).datetime()
+        next_setting = next_setting.strftime("%Y-%m-%d %H:%M:%S")
+        OBS.horizon = previous_horizon
+        return(next_setting)
+
+    def is_nighttime(self,OBS):
+        # Is nightime (sun below a given altitude)
+        timeutc = self.read_datetime()
+        if self.calculate_sun_altitude(OBS,timeutc)*180./math.pi>config._observatory_horizon:
+            return False
+        else:
+            return True
+
+
+
+RAWHeaderContent = '''# Definition of the community standard for skyglow observations 1.0
+# URL: http://www.darksky.org/NSBM/sdf1.0.pdf
+# Number of header lines: 35
+# This data is released under the following license: ODbL 1.0 http://opendatacommons.org/licenses/odbl/summary/
+# Device type: $DEVICE_TYPE
+# Instrument ID: $DEVICE_ID
+# Data supplier: $DATA_SUPPLIER
+# Location name: $LOCATION_NAME
+# Position: $OBSLAT, $OBSLON, $OBSALT
+# Local timezone: $TIMEZONE
+# Time Synchronization: NTP
+# Moving / Stationary position: STATIONARY
+# Moving / Fixed look direction: FIXED
+# Number of channels: 1
+# Filters per channel: HOYA CM-500
+# Measurement direction per channel: 0., 0.
+# Field of view: 20
+# Number of fields per line: 6
+# SQM serial number: $SERIAL_NUMBER
+# SQM firmware version: $FEATURE_NUMBER
+# SQM cover offset value: $OFFSET
+# SQM readout test ix: $IXREADOUT
+# SQM readout test rx: $RXREADOUT
+# SQM readout test cx: $CXREADOUT
+# Comment:
+# Comment:
+# Comment:
+# Comment:
+# Comment: Capture program: PySQM
+# blank line 30
+# blank line 31
+# blank line 32
+# UTC Date & Time, Local Date & Time, Temperature, Counts, Frequency, MSAS
+# YYYY-MM-DDTHH:mm:ss.fff;YYYY-MM-DDTHH:mm:ss.fff;Celsius;number;Hz;mag/arcsec^2
+# END OF HEADER
+'''

pysqm/main.py

+#!/usr/bin/env python
+
+'''
+PySQM main program
+____________________________
+
+Copyright (c) Mireia Nievas <mnievas[at]ucm[dot]es>
+
+This file is part of PySQM.
+
+PySQM is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+PySQM is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with PySQM.  If not, see <http://www.gnu.org/licenses/>.
+____________________________
+'''
+
+import os,sys
+import time
+import datetime
+import argparse
+
+
+'''
+Read input arguments (if any)
+'''
+import pysqm.settings as settings
+InputArguments = settings.ArgParser()
+configfilename = InputArguments.config
+
+# Load config contents into GlobalConfig
+settings.GlobalConfig.read_config_file(configfilename)
+
+# Get the actual config
+config = settings.GlobalConfig.config
+
+### Load now the rest of the modules
+from pysqm.read import *
+import pysqm.plot
+
+'''
+This import section is only for software build purposes.
+Dont worry if some of these are missing in your setup.
+'''
+
+def relaxed_import(themodule):
+    try: exec('import '+str(themodule))
+    except: pass
+
+relaxed_import('socket')
+relaxed_import('serial')
+relaxed_import('_mysql')
+relaxed_import('pysqm.email')
+
+
+'''
+Conditional imports
+'''
+
+# If the old format (SQM_LE/SQM_LU) is used, replace _ with -
+config._device_type = config._device_type.replace('_','-')
+
+if config._device_type == 'SQM-LE':
+    import socket
+elif config._device_type == 'SQM-LU':
+    import serial
+if config._use_mysql == True:
+    import _mysql
+
+
+# Create directories if needed
+for directory in [config.monthly_data_directory,config.daily_data_directory,config.current_data_directory]:
+    if not os.path.exists(directory):
+        os.makedirs(directory)
+
+
+'''
+Select the device to be used based on user input
+and start the measures
+'''
+
+if config._device_type=='SQM-LU':
+    mydevice = SQMLU()
+elif config._device_type=='SQM-LE':
+    mydevice = SQMLE()
+else:
+    print(('ERROR. Unknown device type '+str(config._device_type)))
+    exit(0)
+
+
+def loop():
+    '''
+    Ephem is used to calculate moon position (if above horizon)
+    and to determine start-end times of the measures
+    '''
+    observ = define_ephem_observatory()
+    niter = 0
+    DaytimePrint=True
+    print('Starting readings ...')
+    while 1<2:
+        ''' The programs works as a daemon '''
+        utcdt = mydevice.read_datetime()
+        #print (str(mydevice.local_datetime(utcdt))),
+        if mydevice.is_nighttime(observ):
+            # If we are in a new night, create the new file.
+            config._send_to_datacenter = False ### Not enabled by default
+            try:
+                assert(config._send_to_datacenter == True)
+                assert(niter == 0)
+                mydevice.save_data_datacenter("NEWFILE")
+            except: pass
+
+            StartDateTime = datetime.datetime.now()
+            niter += 1
+
+            mydevice.define_filenames()
+
+            ''' Get values from the photometer '''
+            try:
+                timeutc_mean,timelocal_mean,temp_sensor,\
+                freq_sensor,ticks_uC,sky_brightness = \
+                    mydevice.read_photometer(\
+                     Nmeasures=config._measures_to_promediate,PauseMeasures=10)
+            except:
+                print('Connection lost')
+                if config._reboot_on_connlost == True:
+                    sleep(600)
+                    os.system('reboot.bat')
+
+                time.sleep(1)
+                mydevice.reset_device()
+
+            formatted_data = mydevice.format_content(\
+                timeutc_mean,timelocal_mean,temp_sensor,\
+                freq_sensor,ticks_uC,sky_brightness)
+
+            try:
+                assert(config._use_mysql == True)
+                mydevice.save_data_mysql(formatted_data)
+            except: pass
+
+            try:
+                assert(config._send_to_datacenter == True)
+                mydevice.save_data_datacenter(formatted_data)
+            except: pass
+
+            mydevice.data_cache(formatted_data,number_measures=config._cache_measures,niter=niter)
+
+            if niter%config._plot_each == 0:
+                ''' Each X minutes, plot a new graph '''
+                try: pysqm.plot.make_plot(send_emails=False,write_stats=False)
+                except:
+                    print('Warning: Error plotting data.')
+                    print((sys.exc_info()))
+
+            if DaytimePrint==False:
+                DaytimePrint=True
+
+            MainDeltaSeconds = (datetime.datetime.now()-StartDateTime).total_seconds()
+            time.sleep(max(1,config._delay_between_measures-MainDeltaSeconds))
+
+        else:
+            ''' Daytime, print info '''
+            if DaytimePrint==True:
+                utcdt = utcdt.strftime("%Y-%m-%d %H:%M:%S")
+                print((utcdt), end=' ')
+                print(('. Daytime. Waiting until '+str(mydevice.next_sunset(observ))))
+                DaytimePrint=False
+            if niter>0:
+                mydevice.flush_cache()
+                if config._send_data_by_email==True:
+                    try: pysqm.plot.make_plot(send_emails=True,write_stats=True)
+                    except:
+                        print('Warning: Error plotting data / sending email.')
+                        print((sys.exc_info()))
+
+                else:
+                    try: pysqm.plot.make_plot(send_emails=False,write_stats=True)
+                    except:
+                        print('Warning: Error plotting data.')
+                        print((sys.exc_info()))
+
+                niter = 0
+
+            # Send data that is still in the datacenter buffer
+            try:
+                assert(config._send_to_datacenter == True)
+                mydevice.save_data_datacenter("")
+            except: pass
+
+            time.sleep(300)
+
+

pysqm/settings.py

+#!/usr/bin/env python
+
+'''
+PySQM plotting program
+____________________________
+
+Copyright (c) Mireia Nievas <mnievas[at]ucm[dot]es>
+
+This file is part of PySQM.
+
+PySQM is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+PySQM is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with PySQM.  If not, see <http://www.gnu.org/licenses/>.
+____________________________
+'''
+
+import os,sys
+
+
+class ArgParser:
+    def __init__(self,inputfile=False):
+        self.parse_arguments(inputfile)
+
+    def parse_arguments(self,inputfile):
+        import argparse
+        # Return config filename
+        self.parser = argparse.ArgumentParser()
+        self.parser.add_argument('-c', '--config', default="config.py")
+        if (inputfile):
+            self.parser.add_argument('-i', '--input', default=None)
+        args = self.parser.parse_args()
+        vars(self).update(args.__dict__)
+
+    def print_help(self):
+        self.parser.print_help()
+
+
+class ConfigFile:
+    def __init__(self, path="config.py"):
+        # Guess the selected dir and config filename
+        # Should accept:
+        # - absolute path (inc. filename)
+        # - relative path (inc. filename)
+        # - absolute path (exc. filename)
+        # - relative path (exc. filename)
+        # - shortcouts like ~ . etc
+        self.path = path
+        self.config = None
+
+    def read_config_file(self,path):
+        # Get the absolute path
+        abspath = os.path.abspath(path)
+        # Is a dir? Then add config.py (default filename)
+        if os.path.isdir(abspath):
+            abspath += "/config.py"
+        # split directory and filename
+        directory = os.path.dirname(abspath)
+        filename  = os.path.basename(abspath)
+
+        old_syspath = sys.path
+        sys.path.append(directory)
+        import config
+        self.config = config
+
+# Create an object (by default empty) accessible from everywhere
+# After read_config_file is called, GlobalConfig.config will be accessible
+GlobalConfig = ConfigFile()

setup.py

+#!/usr/bin/env python
+
+from distutils.core import setup
+
+setup(name='pysqm',
+      version='3.1',
+      maintainer='Thorsten Alteholz',
+      maintainer_email='python@alteholz.de',
+      url='https://github.com/alteholz/PySQM',
+      license='GPLv3',
+      description='SQM reading and plotting software',
+      packages=['pysqm'],
+      install_requires=['pyephem','numpy','matplotlib'],
+      classifiers=[
+                   "Programming Language :: C",
+                   "Programming Language :: Cython",
+                   "Programming Language :: Python :: 3",
+                   "Programming Language :: Python :: Implementation :: CPython",
+                   'Development Status :: 3 - Alpha',
+                   "Environment :: Other Environment",
+                   "Intended Audience :: Science/Research",
+                   "License :: OSI Approved :: GNU General Public License (GPL)",
+                   "Operating System :: OS Independent",
+                   "Topic :: Scientific/Engineering :: Astronomy",
+                   ],
+      long_description=open('README.txt').read()
+      )