Move to Python 3 only and include a setup.py script

.gitignore

@@ -2,3 +2,6 @@
 *.swp
 *.swo
 .DS_Store
+build/
+dist/
+pyqn.egg-info/

README.md

@@ -0,0 +1,27 @@
+# pyvalem
+A Python package for handling physical units and quantities.
+
+A very quick overview:
+
+    In [1]: from pyqn.units import Units
+
+    In [2]: u1 = Units('km')
+
+    In [3]: u2 = Units('hr')
+
+    In [4]: u3 = u1/u2
+
+    In [5]: print(u3)
+    km.hr-1
+
+    In [6]: u4 = Units('m/s')
+
+    In [7]: u3.conversion(u4)        # OK: can convert from km/hr to m/s
+    Out[7]: 0.2777777777777778
+
+    In [8]: u3.conversion(u2)        #  Oops: can't convert from km/hr to m!
+    ...
+    UnitsError: Failure in units conversion: units km.hr-1[L.T-1] and hr[T] have
+    different dimensions
+
+For more information and examples, see http://christianhill.co.uk/projects/pyqn

atom_unit.py → pyqn/atom_unit.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # atom_unit.py
 # A class for, and attributes used in the parsing of a single "atom unit"
 # identified by a base unit, SI-prefix and exponent, such as 'kg', 's-1',
@@ -26,20 +25,20 @@
 import sys
 from pyparsing import Word, Group, Literal, Suppress, ParseException, oneOf,\
                       Optional
-from si import si_prefixes
-from base_unit import BaseUnit, base_unit_stems
-from dimensions import Dimensions
+from .si import si_prefixes
+from .base_unit import BaseUnit, base_unit_stems
+from .dimensions import Dimensions
 
 # pyparsing stuff for parsing unit strings:
-caps = u'ABCDEFGHIJKLMNOPQRSTUVWXYZ'
+caps = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'
 lowers = caps.lower()
-letters = u'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz_0'
-digits = u'123456789'
+letters = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz_0'
+digits = '123456789'
 exponent = Word(digits + '-')
-prefix = oneOf(si_prefixes.keys())
-ustem = Word(letters + u'Å' + u'Ω')
-uatom = (Group( u'1' | (Optional(prefix) + ustem)) + Optional(exponent))\
-            | (Group( u'1' | ustem) + Optional(exponent))
+prefix = oneOf(list(si_prefixes.keys()))
+ustem = Word(letters + 'Å' + 'Ω')
+uatom = (Group( '1' | (Optional(prefix) + ustem)) + Optional(exponent))\
+            | (Group( '1' | ustem) + Optional(exponent))
 
 # floating point equality and its negation, to some suitable tolerance
 def feq(f1, f2, tol=1.e-10):
@@ -79,7 +78,7 @@ def __init__(self, prefix, base_unit, exponent=1):
             try:
                 self.si_prefix = si_prefixes[prefix]
             except KeyError:
-                raise UnitsError(u'Invalid or unsupported SI prefix: %s'
+                raise UnitsError('Invalid or unsupported SI prefix: %s'
                                                         % prefix)
             self.si_fac = self.si_prefix.fac
         # now calculate the factor relating this AtomUnit to its
@@ -98,7 +97,7 @@ def parse(self, s_unit_atom):
             uatom_data = uatom.parseString(s_unit_atom)
         except ParseException:
             raise
-            raise UnitsError(u'Invalid unit atom syntax: %s' % s_unit_atom)
+            raise UnitsError('Invalid unit atom syntax: %s' % s_unit_atom)
 
         # uatom_data comes back as (([prefix], <stem>), [exponent])
         if len(uatom_data[0]) == 1:
@@ -128,17 +127,15 @@ def __pow__(self, power):
         """ Return the current AtomUnit raised to a specified power. """
         return AtomUnit(self.prefix, self.base_unit, self.exponent * power)
 
-    def __unicode__(self):
+    def __str__(self):
         """ String representation of this AtomUnit. """
-        s = u''
+        s = ''
         if self.prefix:
             s = self.prefix
-        s_exponent = u''
+        s_exponent = ''
         if self.exponent != 1:
-            s_exponent = unicode(self.exponent)
-        return ''.join([s, unicode(self.base_unit), s_exponent])
-    def __str__(self):
-        return unicode(self).encode('utf-8')
+            s_exponent = str(self.exponent)
+        return ''.join([s, str(self.base_unit), s_exponent])
 
     def prefix_base_eq(self, other):
         """

base_unit.py → pyqn/base_unit.py

@@ -1,9 +1,8 @@
-# -*- coding: utf-8 -*-
 # base_unit.py
 # A class representing a "base unit", identified as a single unit with no
 # prefix or exponent, such as 'g', 'hr', 'bar', 's'.
 #
-# Copyright (C) 2012-2015 Christian Hill
+# Copyright (C) 2012-2016 Christian Hill
 # Department of Physics and Astronomy, University College London
 # [email protected]
 #
@@ -22,7 +21,7 @@
 # You should have received a copy of the GNU General Public License
 # along with PyQn.  If not, see <http://www.gnu.org/licenses/>
 
-from dimensions import *
+from .dimensions import *
 
 class BaseUnit(object):
     """
@@ -83,7 +82,7 @@ def __str__(self):
 BaseUnit('Pa', 'pascal', 'pressure', 1., '', 'Pa', d_pressure),
 BaseUnit('C', 'coulomb', 'charge', 1., '', 'C', d_charge),
 BaseUnit('V', 'volt', 'voltage', 1., '', 'V', d_voltage),
-BaseUnit(u'Ω', 'ohm', 'electric resistance', 1, '', r'\Omega',
+BaseUnit('Ω', 'ohm', 'electric resistance', 1, '', r'\Omega',
          d_voltage / d_current),
 BaseUnit('F', 'farad', 'capacitance', 1., '', 'F', d_charge / d_voltage),
 BaseUnit('Wb', 'weber', 'magnetic flux', 1, '', 'Wb', d_magnetic_flux),
@@ -137,15 +136,15 @@ def __str__(self):
 ]),
 
 ('Non-SI mass units', [
-BaseUnit('u', 'atomic mass unit', 'mass', 1.660538921e-27, '', 'u', d_mass),
-BaseUnit('amu', 'atomic mass unit', 'mass', 1.660538921e-27, '', 'amu', d_mass),
+BaseUnit('u', 'atomic mass unit', 'mass', 1.660538921e-27, '', '', d_mass),
+BaseUnit('amu', 'atomic mass unit', 'mass', 1.660538921e-27, '', 'am', d_mass),
 BaseUnit('Da', 'dalton', 'mass', 1.660538921e-27, '', 'Da', d_mass),
 BaseUnit('m_e', 'electron mass', 'mass', 9.10938291e-31, '', 'm_e', d_mass),
 ]),
 
 ('Non-SI units of length, area and volume', [
 # Non-SI length units
-BaseUnit(u'Å', 'angstrom', 'length', 1.e-10, '', '\AA', d_length),
+BaseUnit('Å', 'angstrom', 'length', 1.e-10, '', '\AA', d_length),
 BaseUnit('a0', 'bohr', 'length', 5.2917721092e-11, '', 'a_0', d_length),
 # Non-SI area units
 BaseUnit('b', 'barn', 'area', 1.e-28, '', 'b', d_area),
@@ -200,7 +199,9 @@ def __str__(self):
 
 ('Miscellaneous units', [
 BaseUnit('Td', 'townsend', 'reduced electric field', 1.e-21, '', 'Td',
-         d_voltage * d_area)
+         d_voltage * d_area),
+BaseUnit('Jy', 'jansky', 'spectral flux density', 1.e-26, '', 'Jy',
+         d_energy / d_area)     # W.m-2.s-1
 ]),
 )
 

dimensions.py → pyqn/dimensions.py

@@ -1,10 +1,9 @@
-# -*- coding: utf-8 -*-
 # dimensions.py
 # A class representing the dimensions of a physical quantity's units, in
 # terms of powers of length (L), mass (M), time (T), temperature (Theta),
 # amount of substance (Q), current (C) and luminous intensity (I).
 #
-# Copyright (C) 2012 Christian Hill
+# Copyright (C) 2012-2016 Christian Hill
 # Department of Physics and Astronomy, University College London
 # [email protected]
 #
@@ -40,7 +39,7 @@ def __init__(self, dims=None, **kwargs):
             if not kwargs:
                 self.dims = dims
             else:
-                print 'bad initialisation of Dimensions object'
+                print('bad initialisation of Dimensions object')
                 sys.exit(1)
         else:
             # initialize by keyword arguments
@@ -53,7 +52,7 @@ def __mul__(self, other):
             new_dims.append(dim + other.dims[i])
         return Dimensions(tuple(new_dims))
 
-    def __div__(self, other):
+    def __truediv__(self, other):
         new_dims = []
         for i, dim in enumerate(self.dims):
             new_dims.append(dim - other.dims[i])

list_base_units.py → pyqn/list_base_units.py

@@ -1,6 +1,4 @@
-# -*- coding: utf-8 -*-
 # list_base_units.py
-from __future__ import print_function
 import sys
 from base_unit import base_units
 
@@ -12,21 +10,21 @@ def list_units_text():
         print('{0:6s} {1:30s} {2:20s}'.format('Unit', 'Name', 'Dimensions'))
         print('{0:6s} {1:30s} {2:20s}'.format('----', '----', '----------'))
         for base_unit in base_unit_group:
-            print(u'{0:6s} {1:30s} {2:20s}'.format(unicode(base_unit.stem),
+            print('{0:6s} {1:30s} {2:20s}'.format(unicode(base_unit.stem),
                 base_unit.name, base_unit.dims))
 
 def list_units_html():
     for group_name, base_unit_group in base_units:
-        print(u'<h4>{0}</h4>'.format(group_name))
-        print(u'<table class="my-table">')
-        print(u'<tr><th>Unit</th><th>Name</th><th>Dimensions</th></tr>')
+        print('<h4>{0}</h4>'.format(group_name))
+        print('<table class="my-table">')
+        print('<tr><th>Unit</th><th>Name</th><th>Dimensions</th></tr>')
         for base_unit in base_unit_group:
             # NB we need to encode('utf-8') to pipe in that encoding to the
             # shell, e.g. to create a file
-            print(u'<tr><td>{0:s}</td><td>{1:s}</td><td>{2:s}</td><td></tr>'
+            print('<tr><td>{0:s}</td><td>{1:s}</td><td>{2:s}</td><td></tr>'
                     .format(unicode(base_unit.stem), base_unit.name,
                             base_unit.dims).encode('utf-8'))
-        print(u'</table>')
+        print('</table>')
 
 
 try:

quantity.py → pyqn/quantity.py

@@ -1,8 +1,7 @@
-# -*- coding: utf-8 -*-
 # quantity.py
 # A class representing physical quantity, with name, units and uncertainty.
 #
-# Copyright (C) 2012 Christian Hill
+# Copyright (C) 2012-2016 Christian Hill
 # Department of Physics and Astronomy, University College London
 # [email protected]
 #
@@ -23,8 +22,8 @@
 
 import re
 import math
-from symbol import Symbol
-from units import Units, UnitsError
+from .symbol import Symbol
+from .units import Units, UnitsError
 
 class QuantityError(Exception):
     """
@@ -231,7 +230,7 @@ def __mul__(self, other):
             units = self.units * other.units
             return Quantity(value=value, units=units, sd=sd)
 
-    def __div__(self, other):
+    def __truediv__(self, other):
         """
         Divide this quantity by a number or another quantity. Errors are
         propagated, but assumed to be uncorrelated.

si.py → pyqn/si.py

@@ -1,10 +1,9 @@
-# -*- coding: utf-8 -*-
 # si.py
 # A class representing the SI prefixes (SIPrefix) and a list of the SI
 # base units (si_unit_stems): length (L), mass (M), time (T), temperature
 # (Theta), amount of substance (Q), current (C) and luminous intensity (I).
 #
-# Copyright (C) 2012 Christian Hill
+# Copyright (C) 2012-2016 Christian Hill
 # Department of Physics and Astronomy, University College London
 # [email protected]
 #
@@ -32,27 +31,27 @@ def __init__(self, prefix, name, power):
         self.fac = 10**power
 
 # Here are the SI prefixes that we recognise.
-si_prefixes = { u'y': SIPrefix(u'y', 'yocto', -24),
-                u'z': SIPrefix(u'z', 'zepto', -21),
-                u'a': SIPrefix(u'a', 'atto', -18),
-                u'f': SIPrefix(u'f', 'femto', -15),
-                u'p': SIPrefix(u'p', 'pico', -12),
-                u'n': SIPrefix(u'n', 'nano', -9),
-                u'μ': SIPrefix(u'μ', 'micro', -6),
-                u'm': SIPrefix(u'm', 'milli', -3),
-                u'c': SIPrefix(u'c', 'centi', -2),
-                u'd': SIPrefix(u'd', 'deci', -1),
-                u'k': SIPrefix(u'k', 'kilo', 3),
-                u'M': SIPrefix(u'M', 'mega', 6),
-                u'G': SIPrefix(u'G', 'giga', 9),
-                u'T': SIPrefix(u'T', 'tera', 12),
-                u'P': SIPrefix(u'P', 'peta', 15),
-                u'E': SIPrefix(u'E', 'exa', 18),
-                u'Z': SIPrefix(u'Z', 'zetta', 21),
-                u'Y': SIPrefix(u'Y', 'yotta', 24),
+si_prefixes = { 'y': SIPrefix('y', 'yocto', -24),
+                'z': SIPrefix('z', 'zepto', -21),
+                'a': SIPrefix('a', 'atto', -18),
+                'f': SIPrefix('f', 'femto', -15),
+                'p': SIPrefix('p', 'pico', -12),
+                'n': SIPrefix('n', 'nano', -9),
+                'μ': SIPrefix('μ', 'micro', -6),
+                'm': SIPrefix('m', 'milli', -3),
+                'c': SIPrefix('c', 'centi', -2),
+                'd': SIPrefix('d', 'deci', -1),
+                'k': SIPrefix('k', 'kilo', 3),
+                'M': SIPrefix('M', 'mega', 6),
+                'G': SIPrefix('G', 'giga', 9),
+                'T': SIPrefix('T', 'tera', 12),
+                'P': SIPrefix('P', 'peta', 15),
+                'E': SIPrefix('E', 'exa', 18),
+                'Z': SIPrefix('Z', 'zetta', 21),
+                'Y': SIPrefix('Y', 'yotta', 24),
               }
 
 # The base SI unit stems for length, time, mass, amount of substance,
 # thermodynamic temperature, luminous intenstiy and current respectively:
-si_unit_stems = (u'm', u's', u'g', u'mol', u'K', u'cd', u'A')
+si_unit_stems = ('m', 's', 'g', 'mol', 'K', 'cd', 'A')
 

symbol.py → pyqn/symbol.py

@@ -1,9 +1,8 @@
-# -*- coding: utf-8 -*-
 # symbol.py
 # A class representing a symbol (perhaps the label for a physical quantity
 # represented as a Quantity object) with a name in text,  LaTeX and HTML.
 #
-# Copyright (C) 2012 Christian Hill
+# Copyright (C) 2012-2016 Christian Hill
 # Department of Physics and Astronomy, University College London
 # [email protected]
 #

test_units.py → pyqn/tests/test_units.py

@@ -1,10 +1,12 @@
-# -*- coding: utf-8 -*-
 # test_units.py
-# Version 0.1a
+#
+# Copyright (C) 2012-2016 Christian Hill
+#
+# Version 1.0
 # Unit tests for the Units class.
 
 import unittest
-from units import Units
+from ..units import Units
 
 class UnitsCheck(unittest.TestCase):
     """Unit tests for the Units class."""
@@ -27,8 +29,8 @@ def test_units_algebra(self):
         self.assertFalse(u3_over_u4.has_units())
 
     def test_unicode_units(self):
-        u1 = Units(u'kΩ')
-        self.assertEqual(unicode(u1), u'kΩ')
+        u1 = Units('kΩ')
+        self.assertEqual(str(u1), 'kΩ')
 
 if __name__ == '__main__':
     unittest.main()

test_units_collisions.py → pyqn/tests/test_units_collisions.py

@@ -1,14 +1,16 @@
-#! -*- coding: utf-8 -*-
 # test_units_collisions.py
-# Version 0.1a
+#
+# Copyright (C) 2012-2016 Christian Hill
+#
+# Version 1.0
 # Check for conflicts amongst derived and base units. For example, inches
 # can't be called "in" because the milli-inch, "min" conflicts with the use
 # of "min" for minutes.
 
 import unittest
-from units import Units
-from base_unit import base_units
-from si import si_prefixes
+from ..units import Units
+from ..base_unit import base_units
+from ..si import si_prefixes
 
 class ConflictsCheck(unittest.TestCase):
     """
@@ -18,10 +20,10 @@ class ConflictsCheck(unittest.TestCase):
     """
 
     def test_units_conflicts(self):
+        prefixes = ['']; prefixes.extend(si_prefixes)
         seen_units = []
         for base_unit_group in base_units:
             for base_unit in base_unit_group[1]:
-                prefixes = ['']; prefixes.extend(si_prefixes)
                 for si_prefix in prefixes:
                     this_unit = '%s%s' % (si_prefix, base_unit.stem)
                     self.assertEqual(this_unit in seen_units, False,