added latin/greek keywords to index command

.github/workflows/main.yaml

@@ -10,7 +10,7 @@ jobs:
       - name: install python
         uses: actions/setup-python@v4
         with:
-          python-version: 3.7
+          python-version: 3.8.x
       - name: install sympy (latest stable version)
         run: python -m pip install ipython sympy
       - name: perform unit testing
@@ -24,7 +24,7 @@ jobs:
       - name: install python
         uses: actions/setup-python@v4
         with:
-          python-version: 3.7
+          python-version: 3.8.x
       - name: install sympy (latest stable version)
         run: python -m pip install ipython sympy
       - name: perform unit testing
@@ -38,7 +38,7 @@ jobs:
       - name: install python
         uses: actions/setup-python@v4
         with:
-          python-version: 3.7
+          python-version: 3.8.x
       - name: install sympy (latest stable version)
         run: python -m pip install ipython sympy
       - name: perform unit testing
@@ -52,7 +52,7 @@ jobs:
       - name: install python
         uses: actions/setup-python@v4
         with:
-          python-version: 3.6
+          python-version: 3.8.x
       - name: install sympy (earliest supported version)
         run: python -m pip install ipython sympy==1.2
       - name: perform unit testing
@@ -66,7 +66,7 @@ jobs:
       - name: install python
         uses: actions/setup-python@v4
         with:
-          python-version: 3.8
+          python-version: 3.8.x
       - name: install ipython
         run: python -m pip install ipython
       - name: install sympy (latest development version)

nrpylatex/core/parser.py

@@ -14,6 +14,13 @@
 from collections import OrderedDict
 import re
 
+LATIN_ALPHABET = [chr(i) for i in range(97, 123)]
+GREEK_ALPHABET = [
+    'alpha', 'beta', 'gamma', 'delta', 'epsilon', 'zeta', 'eta', 'theta',
+    'iota', 'kappa', 'lambda', 'mu', 'nu', 'xi', 'omikron', 'pi', 'rho',
+    'sigma', 'tau', 'upsilon', 'phi', 'chi', 'psi', 'omega'
+]
+
 class Parser:
 
     _namespace, _property = OrderedDict(), {}
@@ -33,12 +40,8 @@ def initialize(reset=False):
         if reset: Parser._namespace.clear()
         Parser._property['replace'] = []
         Parser._property['coord'] = CoordinateSystem('x')
-        Parser._property['index'] = {chr(i): 3 for i in range(97, 123)}
-        Parser._property['index'].update({i: 4 for i in [
-            'alpha', 'beta', 'gamma', 'delta', 'epsilon', 'zeta', 'eta', 'theta',
-            'iota', 'kappa', 'lambda', 'mu', 'nu', 'xi', 'omikron', 'pi', 'rho',
-            'sigma', 'tau', 'upsilon', 'phi', 'chi', 'psi', 'omega'
-        ]})
+        Parser._property['index'] = {index: 3 for index in LATIN_ALPHABET}
+        Parser._property['index'].update({index: 4 for index in GREEK_ALPHABET})
         Parser._property['ignore'] = ['\\left', '\\right', '{}', '&']
         Parser._property['metric'] = {'': '', 'bar': '', 'hat': '', 'tilde': ''}
         Parser._property['suffix'] = 'dD'
@@ -149,10 +152,10 @@ def _declare(self):
         while True:
             symbols.append(self.scanner.lexeme)
             self.expect('IDENTIFIER')
-            if self.peek('LDASH') or self.peek('LINEBREAK'): break
+            if self.peek('DBL_DASH') or self.peek('LINEBREAK'): break
         dimension = symmetry = weight = suffix = metric = None
         const = zeros = False
-        while self.accept('LDASH'):
+        while self.accept('DBL_DASH'):
             if self.accept('CONST_OPT'):
                 const = True
             elif self.accept('ZEROS_OPT'):
@@ -257,7 +260,7 @@ def _replace(self):
         self.scanner.lex()
         self.accept('LINEBREAK')
 
-    # <COORD> -> <COORD_KWD> { <IDENTIFIER> }*
+    # <COORD> -> <COORD_KWD> ( { <IDENTIFIER> }+ | <DEFAULT_KWD> )
     def _coord(self):
         self.expect('COORD_KWD')
         del self._property['coord'][:]
@@ -272,33 +275,33 @@ def _coord(self):
                         (sentence[position], position), sentence, position)
                 self._property['coord'].append(symbol)
                 if self.peek('LINEBREAK'): break
-        else:
+        elif self.accept('DEFAULT_KWD'):
             self._property['coord'] = CoordinateSystem('x')
+        else:
+            sentence, (position, _) = self.scanner.sentence, self.scanner.prev_state
+            raise ParserError('unexpected \'%s\' at position %d' %
+                (sentence[position], position), sentence, position)
         self.accept('LINEBREAK')
 
-    # <INDEX> -> <INDEX_KWD> { <IDENTIFIER> [ '..' <IDENTIFIER> ] }* '--' <DIM_OPT> <INTEGER>
+    # <INDEX> -> <INDEX_KWD> ( { <IDENTIFIER> }+ | <LATIN_KWD> | <GREEK_KWD> ) '--' <DIM_OPT> <INTEGER>
     def _index(self):
         self.expect('INDEX_KWD')
         indices = []
         if self.peek('IDENTIFIER'):
             while True:
                 sentence, (position, _) = self.scanner.sentence, self.scanner.prev_state
-                index_1 = self.scanner.lexeme
+                indices.append(self.scanner.lexeme)
                 self.expect('IDENTIFIER')
-                if self.accept('LDOTS'):
-                    index_2 = self.scanner.lexeme
-                    self.expect('IDENTIFIER')
-                    try:
-                        indices.extend([chr(i) for i in range(ord(index_1), ord(index_2) + 1)])
-                    except TypeError:
-                        raise ParserError('unsupported index range \'%s\' at position %d' %
-                            (sentence[position:self.scanner.position], position), sentence, position)
-                else:
-                    indices.append(index_1)
-                if self.peek('LDASH'): break
+                if self.peek('DBL_DASH'): break
+        elif self.accept('LATIN_KWD'):
+            indices.extend([index for index in LATIN_ALPHABET])
+        elif self.accept('GREEK_KWD'):
+            indices.extend([index for index in GREEK_ALPHABET])
         else:
-            indices.extend([index for index in self._property['index']])
-        self.expect('LDASH')
+            sentence, (position, _) = self.scanner.sentence, self.scanner.prev_state
+            raise ParserError('unexpected \'%s\' at position %d' %
+                (sentence[position], position), sentence, position)
+        self.expect('DBL_DASH')
         self.expect('DIM_OPT')
         dimension = self.scanner.lexeme
         self.expect('INTEGER')
@@ -313,10 +316,10 @@ def _metric(self):
         while True:
             symbols.append(self.scanner.lexeme)
             self.expect('IDENTIFIER')
-            if self.peek('LDASH') or self.peek('LINEBREAK'): break
+            if self.peek('DBL_DASH') or self.peek('LINEBREAK'): break
         dimension = suffix = None
         zeros = False
-        while self.accept('LDASH'):
+        while self.accept('DBL_DASH'):
             if self.accept('ZEROS_OPT'):
                 zeros = True
             else:

nrpylatex/core/scanner.py

@@ -26,8 +26,7 @@ def __init__(self):
             ('PERCENT',         r'\%'),
             ('STRING',          r'\"[^\"]*\"'),
             ('ARROW',           r'\-\>'),
-            ('LDASH',           r'\-\-'),
-            ('LDOTS',           r'\.\.'),
+            ('DBL_DASH',        r'\-\-'),
             ('SYMMETRY',        symmetry),
             ('ZEROS_OPT',       r'zeros'),
             ('CONST_OPT',       r'const'),
@@ -37,7 +36,10 @@ def __init__(self):
             ('SUFFIX_OPT',      r'suffix'),
             ('METRIC_OPT',      r'metric'),
             ('COORD_KWD',       r'coord'),
+            ('DEFAULT_KWD',     r'default'),
             ('INDEX_KWD',       r'index'),
+            ('LATIN_KWD',       r'latin'),
+            ('GREEK_KWD',       r'greek'),
             ('IDENTIFIER',      alphabet + r'((%s)|[_0-9])*' % alphabet),
             ('INTEGER',         r'[0-9]+'),
             ('NEWLINE',         r'\\{2}')]

nrpylatex/tests/test_parse_latex.py

@@ -129,7 +129,7 @@ def test_recursive_replacement(self):
     def test_product_rule(self):
         self.assertEqual(
             set(parse_latex(r"""
-                % declare index --dim 2
+                % declare index latin --dim 2
                 % declare vU wU --dim 2 --suffix dD
                 T^{ab}_c = \partial_c (v^a w^b)
             """)),
@@ -142,7 +142,7 @@ def test_product_rule(self):
     def test_upwind_suffix(self):
         self.assertEqual(
             set(parse_latex(r"""
-                % declare index --dim 2
+                % declare index latin --dim 2
                 % declare vU --dim 2 --suffix dD
                 % declare w --const
                 T^a_c = % suffix dupD
@@ -157,7 +157,7 @@ def test_upwind_suffix(self):
     def test_inference_covdrv(self):
         self.assertEqual(
             set(parse_latex(r"""
-                % declare index --dim 4
+                % declare index latin --dim 4
                 % declare metric gDD --dim 4 --suffix dD
                 % declare vU --dim 4 --suffix dD
                 T^{ab} = \nabla^b v^a
@@ -169,7 +169,7 @@ def test_inference_pardrv(self):
         self.assertEqual(
             set(parse_latex(r"""
                 % declare coord x y
-                % declare index --dim 2
+                % declare index latin --dim 2
                 % declare uD --zeros --dim 2
                 u_x = x^2 + 2x \\
                 u_y = y\sqrt{x}
@@ -186,7 +186,7 @@ def test_inference_pardrv(self):
     def test_notation_pardrv(self):
         self.assertEqual(
             set(parse_latex(r"""
-                % declare index --dim 2
+                % declare index latin --dim 2
                 % declare vD uD wD --dim 2 --suffix dD
                 T_{abc} = ((v_a + u_a)_{,b} - w_{a,b})_{,c}
             """)),
@@ -199,7 +199,8 @@ def test_notation_pardrv(self):
     def test_spherical_riemann(self):
         parse_latex(r"""
             % declare coord theta phi
-            % declare index --dim 2
+            % declare index latin --dim 2
+            % declare index greek --dim 2
             % declare metric gDD --zeros --dim 2
             % declare r --const
             % g_{0 0} = r^2 \\
@@ -563,7 +564,7 @@ def test_inverse_covariant(self):
         for DIM in range(2, 5):
             parse_latex(r"""
                 % declare metric gDD --dim {DIM}
-                % declare index --dim {DIM}
+                % declare index latin --dim {DIM}
                 T^a_c = g^{{ab}} g_{{bc}}
             """.format(DIM=DIM))
             for i in range(DIM):
@@ -574,7 +575,7 @@ def test_inverse_contravariant(self):
         for DIM in range(2, 5):
             parse_latex(r"""
                 % declare metric gUU --dim {DIM}
-                % declare index --dim {DIM}
+                % declare index latin --dim {DIM}
                 T^a_c = g^{{ab}} g_{{bc}}
             """.format(DIM=DIM))
             for i in range(DIM):