Switch quantities over to f-strings

quantities/decorators.py

@@ -42,11 +42,11 @@ def __call__(self, new_method):
         header = self.header
 
         if original_doc and new_doc:
-            new_method.__doc__ = """
-    {}
-    {}
-    {}
-        """.format(original_doc, header, new_doc)
+            new_method.__doc__ = f"""
+    {original_doc}
+    {header}
+    {new_doc}
+        """
 
         elif original_doc:
             new_method.__doc__ = original_doc

quantities/dimensionality.py

@@ -69,8 +69,7 @@ def __add__(self, other):
             assert self == other
         except AssertionError:
             raise ValueError(
-                'can not add units of %s and %s'\
-                %(str(self), str(other))
+                f'can not add units of {str(self)} and {str(other)}'
             )
         return self.copy()
 
@@ -82,8 +81,7 @@ def __iadd__(self, other):
             assert self == other
         except AssertionError:
             raise ValueError(
-                'can not add units of %s and %s'\
-                %(str(self), str(other))
+                f'can not add units of {str(self)} and {str(other)}'
             )
         return self
 
@@ -93,8 +91,7 @@ def __sub__(self, other):
             assert self == other
         except AssertionError:
             raise ValueError(
-                'can not subtract units of %s and %s'\
-                %(str(self), str(other))
+                f'can not subtract units of {str(self)} and {str(other)}'
             )
         return self.copy()
 
@@ -106,8 +103,7 @@ def __isub__(self, other):
             assert self == other
         except AssertionError:
             raise ValueError(
-                'can not add units of %s and %s'\
-                %(str(self), str(other))
+                f'can not add units of {str(self)} and {str(other)}'
             )
         return self
 
@@ -161,7 +157,7 @@ def __pow__(self, other):
         try:
             assert np.isscalar(other)
         except AssertionError:
-            raise TypeError('exponent must be a scalar, got %r' % other)
+            raise TypeError(f'exponent must be a scalar, got {other!r}')
         if other == 0:
             return Dimensionality()
         new = Dimensionality(self)
@@ -173,7 +169,7 @@ def __ipow__(self, other):
         try:
             assert np.isscalar(other)
         except AssertionError:
-            raise TypeError('exponent must be a scalar, got %r' % other)
+            raise TypeError(f'exponent must be a scalar, got {other!r}')
         if other == 0:
             self.clear()
             return self
@@ -246,8 +242,7 @@ def _d_check_uniform(q1, q2, out=None):
         return q1.dimensionality
     except AssertionError:
         raise ValueError(
-            'quantities must have identical units, got "%s" and "%s"' %
-            (q1.units, q2.units)
+            f'quantities must have identical units, got "{q1.units}" and "{q2.units}"'
         )
     except AttributeError:
         try:
@@ -265,8 +260,7 @@ def _d_check_uniform(q1, q2, out=None):
                     raise ValueError
         except ValueError:
             raise ValueError(
-                'quantities must have identical units, got "%s" and "%s"' %
-                (q1.units, q2.units)
+                f'quantities must have identical units, got "{q1.units}" and "{q2.units}"'
             )
 
 p_dict[np.add] = _d_check_uniform
@@ -288,8 +282,7 @@ def _d_arctan2(q1, q2, out=None):
         return Dimensionality()
     except AssertionError:
         raise ValueError(
-            'quantities must have identical units, got "%s" and "%s"' %
-            (q1.units, q2.units)
+            f'quantities must have identical units, got "{q1.units}" and "{q2.units}"'
         )
 
 p_dict[np.arctan2] = _d_arctan2
@@ -343,7 +336,7 @@ def _d_radians(q1, out=None):
         assert q1.units == unit_registry['degree']
     except AssertionError:
         raise ValueError(
-            'expected units of degrees, got "%s"' % q1._dimensionality
+            f'expected units of degrees, got "{q1._dimensionality}"'
         )
     return unit_registry['radian'].dimensionality
 p_dict[np.radians] = _d_radians
@@ -353,7 +346,7 @@ def _d_degrees(q1, out=None):
         assert q1.units == unit_registry['radian']
     except AssertionError:
         raise ValueError(
-            'expected units of radians, got "%s"' % q1._dimensionality
+            f'expected units of radians, got "{q1._dimensionality}"'
         )
     return unit_registry['degree'].dimensionality
 p_dict[np.degrees] = _d_degrees
@@ -377,7 +370,7 @@ def _d_trig(q1, out=None):
         assert q1.units == unit_registry['radian']
     except AssertionError:
         raise ValueError(
-            'expected units of radians, got "%s"' % q1._dimensionality
+            f'expected units of radians, got "{q1._dimensionality}"'
         )
     return Dimensionality()
 p_dict[np.sin] = _d_trig

quantities/markup.py

@@ -61,12 +61,12 @@ def format_units(udict):
             u = key.symbol
         if d>0:
             if d != 1:
-                u = u + ('**%s'%d).rstrip('0').rstrip('.')
+                u = u + f'**{d}'.rstrip('0').rstrip('.')
             num.append(u)
         elif d<0:
             d = -d
             if d != 1:
-                u = u + ('**%s'%d).rstrip('0').rstrip('.')
+                u = u + f'**{d}'.rstrip('0').rstrip('.')
             den.append(u)
     res = '*'.join(num)
     if len(den):
@@ -156,6 +156,6 @@ def format_units_html(udict,font='%s',mult=r'&sdot;',paren=False):
     # Remove multiplication signs
     res = re.sub(r'\*',mult,res)
     if paren and not compound:
-        res = '(%s)' % res
+        res = f'({res})'
     res = font % res
     return res

quantities/quantity.py

@@ -22,8 +22,7 @@ def validate_unit_quantity(value):
         assert value.magnitude == 1
     except AssertionError:
         raise ValueError(
-                'units must be a scalar Quantity with unit magnitude, got %s'\
-                %value
+                f'units must be a scalar Quantity with unit magnitude, got {value}'
             )
     return value
 
@@ -40,8 +39,7 @@ def validate_dimensionality(value):
         return value.copy()
     else:
         raise TypeError(
-            'units must be a quantity, string, or dimensionality, got %s'\
-            %type(value)
+            f'units must be a quantity, string, or dimensionality, got {type(value)}'
         )
 
 def get_conversion_factor(from_u, to_u):
@@ -187,8 +185,7 @@ def units(self, units):
             cf = get_conversion_factor(from_u, to_u)
         except AssertionError:
             raise ValueError(
-                'Unable to convert between units of "%s" and "%s"'
-                %(from_u._dimensionality, to_u._dimensionality)
+                f'Unable to convert between units of "{from_u._dimensionality}" and "{to_u._dimensionality}"'
             )
         mag = self.magnitude
         mag *= cf
@@ -204,7 +201,7 @@ def rescale(self, units=None, dtype=None):
             try:
                 return self.rescale_preferred()
             except Exception as e:
-                raise Exception('No argument passed to `.rescale` and %s' % e)
+                raise Exception(f'No argument passed to `.rescale` and {e}')
         to_dims = validate_dimensionality(units)
         if dtype is None:
             dtype = self.dtype
@@ -216,8 +213,7 @@ def rescale(self, units=None, dtype=None):
             cf = get_conversion_factor(from_u, to_u)
         except AssertionError:
             raise ValueError(
-                'Unable to convert between units of "%s" and "%s"'
-                %(from_u._dimensionality, to_u._dimensionality)
+                f'Unable to convert between units of "{from_u._dimensionality}" and "{to_u._dimensionality}"'
             )
         new_magnitude = cf*self.magnitude
         dtype = np.result_type(dtype, new_magnitude)
@@ -277,9 +273,9 @@ def __array_prepare__(self, obj, context=None):
             res._dimensionality = p_dict[uf](*objs)
         except KeyError:
             raise ValueError(
-                """ufunc %r not supported by quantities
+                f"""ufunc {uf!r} not supported by quantities
                 please file a bug report at https://github.com/python-quantities
-                """ % uf
+                """
                 )
         return res
 
@@ -367,17 +363,15 @@ def __round__(self, decimals=0):
 
     @with_doc(np.ndarray.__repr__)
     def __repr__(self):
-        return '%s * %s'%(
-            repr(self.magnitude), self.dimensionality.string
-        )
+        return f'{repr(self.magnitude)} * {self.dimensionality.string}'
 
     @with_doc(np.ndarray.__str__)
     def __str__(self):
         if markup.config.use_unicode:
             dims = self.dimensionality.unicode
         else:
             dims = self.dimensionality.string
-        return '%s %s'%(str(self.magnitude), dims)
+        return f'{str(self.magnitude)} {dims}'
 
     if tuple(map(int, np.__version__.split('.')[:2])) >= (1, 14):
         # in numpy 1.14 the formatting of scalar values was changed

quantities/registry.py

@@ -21,7 +21,7 @@ def __getitem__(self, string):
             except NameError:
                 # could return self['UnitQuantity'](string)
                 raise LookupError(
-                    'Unable to parse units: "%s"'%string
+                    f'Unable to parse units: "{string}"'
                 )
 
         def __setitem__(self, string, val):
@@ -32,8 +32,7 @@ def __setitem__(self, string, val):
                 if val == self.__context[string]:
                     return
                 raise KeyError(
-                    '%s has already been registered for %s'
-                    % (string, self.__context[string])
+                    f'{string} has already been registered for {self.__context[string]}'
                 )
             self.__context[string] = val
 

quantities/tests/common.py

@@ -20,7 +20,7 @@ def assertQuantityEqual(self, q1, q2, msg=None, delta=None):
         precision.
         """
         delta = 1e-5 if delta is None else delta
-        msg = '' if msg is None else ' (%s)' % msg
+        msg = '' if msg is None else f' ({msg})'
 
         q1 = Quantity(q1)
         q2 = Quantity(q2)
@@ -30,8 +30,7 @@ def assertQuantityEqual(self, q1, q2, msg=None, delta=None):
                 )
         if not np.all(np.abs(q1.magnitude - q2.magnitude) < delta):
             raise self.failureException(
-                "Magnitudes differ by more than %g (%s vs %s)%s"
-                % (delta, q1.magnitude, q2.magnitude, msg)
+                f"Magnitudes differ by more than {delta:g} ({q1.magnitude} vs {q2.magnitude}){msg}"
                 )
 
         d1 = getattr(q1, '_dimensionality', None)

quantities/tests/test_units.py

@@ -17,7 +17,7 @@ def setunits(u, v):
             u.units = v
 
         def inplace(op, u, val):
-            getattr(u, '__i%s__'%op)(val)
+            getattr(u, f'__i{op}__')(val)
 
         self.assertRaises(AttributeError, setunits, pq.m, pq.ft)
         self.assertRaises(TypeError, inplace, 'add', pq.m, pq.m)

quantities/umath.py

@@ -344,8 +344,7 @@ def arctan2(x1, x2, out=None):
 
     if x1._dimensionality.simplified != x2._dimensionality.simplified:
         raise ValueError(
-            'x1 and x2 must have identical units, got "%s" and "%s"'\
-            % (str(x1._dimensionality), str(x2._dimensionality))
+            f'x1 and x2 must have identical units, got "{str(x1._dimensionality)}" and "{str(x2._dimensionality)}"'
         )
 
     return Quantity(
@@ -369,8 +368,7 @@ def hypot(x1, x2, out = None):
 
     if x1._dimensionality != x2._dimensionality:
         raise ValueError(
-            'x1 and x2 must have identical units, got "%s" and "%s"'\
-            % (str(x1._dimensionality), str(x2._dimensionality))
+            f'x1 and x2 must have identical units, got "{str(x1._dimensionality)}" and "{str(x2._dimensionality)}"'
         )
 
     return Quantity(

quantities/uncertainquantity.py

@@ -184,11 +184,7 @@ def __str__(self):
             dims = self.dimensionality.unicode
         else:
             dims = self.dimensionality.string
-        s = '%s %s\n+/-%s (1 sigma)'%(
-            str(self.magnitude),
-            dims,
-            str(self.uncertainty)
-        )
+        s = f'{str(self.magnitude)} {dims}\n+/-{str(self.uncertainty)} (1 sigma)'
         if markup.config.use_unicode:
             return s.replace('+/-', '±').replace(' sigma', 'σ')
         return s

quantities/unitquantity.py

@@ -35,13 +35,12 @@ def __new__(
         try:
             assert isinstance(name, str)
         except AssertionError:
-            raise TypeError('name must be a string, got %s (not unicode)'%name)
+            raise TypeError(f'name must be a string, got {name} (not unicode)')
         try:
             assert symbol is None or isinstance(symbol, str)
         except AssertionError:
             raise TypeError(
-                'symbol must be a string, '
-                'got %s (u_symbol can be unicode)'%symbol
+                f'symbol must be a string, got {symbol} (u_symbol can be unicode)'
             )
 
         ret = numpy.array(1, dtype='d').view(cls)
@@ -139,29 +138,27 @@ def units(self, units):
     def __repr__(self):
         ref = self._definition
         if ref:
-            ref = ', %s * %s'%(str(ref.magnitude), ref.dimensionality.string)
+            ref = f', {str(ref.magnitude)} * {ref.dimensionality.string}'
         else:
             ref = ''
         symbol = self._symbol
-        symbol = ', %s'%(repr(symbol)) if symbol else ''
+        symbol = f', {repr(symbol)}' if symbol else ''
         if markup.config.use_unicode:
             u_symbol = self._u_symbol
-            u_symbol = ', %s'%(repr(u_symbol)) if u_symbol else ''
+            u_symbol = f', {repr(u_symbol)}' if u_symbol else ''
         else:
             u_symbol = ''
-        return '%s(%s%s%s%s)'%(
-            self.__class__.__name__, repr(self.name), ref, symbol, u_symbol
-        )
+        return f'{self.__class__.__name__}({repr(self.name)}{ref}{symbol}{u_symbol})'
 
     @with_doc(Quantity.__str__, use_header=False)
     def __str__(self):
         if self.u_symbol != self.name:
             if markup.config.use_unicode:
-                s = '1 %s (%s)'%(self.u_symbol, self.name)
+                s = f'1 {self.u_symbol} ({self.name})'
             else:
-                s = '1 %s (%s)'%(self.symbol, self.name)
+                s = f'1 {self.symbol} ({self.name})'
         else:
-            s = '1 %s'%self.name
+            s = f'1 {self.name}'
 
         return s
 
@@ -381,14 +378,14 @@ def __init__(self, name):
 
     @with_doc(UnitQuantity.__add__, use_header=False)
     def __repr__(self):
-        return '1 %s'%self.name
+        return f'1 {self.name}'
 
     @property
     def name(self):
         if markup.config.use_unicode:
-            return '(%s)'%(markup.superscript(self._name))
+            return f'({markup.superscript(self._name)})'
         else:
-            return '(%s)'%self._name
+            return f'({self._name})'
 
     def __reduce__(self):
         """
@@ -476,7 +473,7 @@ def set_default_units(
         try:
             assert system in ('si', 'cgs')
         except AssertionError:
-            raise ValueError('system must be "SI" or "cgs", got "%s"' % system)
+            raise ValueError(f'system must be "SI" or "cgs", got "{system}"')
         if system == 'si':
             UnitCurrent.set_default_unit('A')
             UnitLength.set_default_unit('m')