Adding pytests for from_sympy / to_sympy.

mathics/builtin/__init__.py

@@ -50,6 +50,8 @@
 
 
 def add_builtins(new_builtins):
+    from mathics.core.convert.sympy import mathics_to_sympy, sympy_to_mathics
+
     for var_name, builtin in new_builtins:
         name = builtin.get_name()
         if hasattr(builtin, "python_equivalent"):
@@ -237,8 +239,6 @@ def name_is_builtin_symbol(module, name: str) -> Optional[type]:
                 _builtins_list.append((instance.get_name(), instance))
                 builtins_by_module[module.__name__].append(instance)
 
-mathics_to_sympy = {}  # here we have: name -> sympy object
-sympy_to_mathics = {}
 
 new_builtins = _builtins_list
 

mathics/builtin/arithmetic.py

@@ -18,6 +18,7 @@
     IterationFunction,
     Predefined,
     SympyFunction,
+    SympyObject,
     Test,
 )
 from mathics.builtin.inference import evaluate_predicate, get_assumptions_list
@@ -767,7 +768,7 @@ def eval_Element_alternatives(
         return Element(Expression(elems.head, *unknown), domain)
 
 
-class I_(Predefined):
+class I_(Predefined, SympyObject):
     """
     <url>:Imaginary unit:https://en.wikipedia.org/wiki/Imaginary_unit</url> \
     (<url>:WMA:https://reference.wolfram.com/language/ref/I.html</url>)
@@ -784,9 +785,17 @@ class I_(Predefined):
     """
 
     name = "I"
+    sympy_name = "I"
+    sympy_obj = sympy.I
     summary_text = "imaginary unit"
     python_equivalent = 1j
 
+    def is_constant(self) -> bool:
+        return True
+
+    def to_sympy(self, symb, **kwargs):
+        return self.sympy_obj
+
     def evaluate(self, evaluation: Evaluation):
         return Complex(Integer0, Integer1)
 

mathics/builtin/base.py

@@ -19,10 +19,10 @@
     String,
 )
 from mathics.core.attributes import A_HOLD_ALL, A_NO_ATTRIBUTES, A_PROTECTED
-from mathics.core.convert.expression import to_expression, to_numeric_sympy_args
+from mathics.core.convert.expression import to_expression
 from mathics.core.convert.op import ascii_operator_to_symbol
 from mathics.core.convert.python import from_bool
-from mathics.core.convert.sympy import from_sympy
+from mathics.core.convert.sympy import from_sympy, to_numeric_sympy_args
 from mathics.core.definitions import Definition
 from mathics.core.evaluation import Evaluation
 from mathics.core.exceptions import MessageException

mathics/builtin/specialfns/elliptic.py

@@ -15,8 +15,7 @@
 from mathics.builtin.base import SympyFunction
 from mathics.core.atoms import Integer
 from mathics.core.attributes import A_LISTABLE, A_NUMERIC_FUNCTION, A_PROTECTED
-from mathics.core.convert.expression import to_numeric_sympy_args
-from mathics.core.convert.sympy import from_sympy
+from mathics.core.convert.sympy import from_sympy, to_numeric_sympy_args
 from mathics.eval.numerify import numerify
 
 

mathics/core/atoms.py

@@ -942,6 +942,8 @@ def is_zero(self) -> bool:
 
 
 RationalOneHalf = Rational(1, 2)
+MATHICS3_COMPLEX_I = Complex(Integer0, Integer1)
+MATHICS3_COMPLEX_I_NEG = Complex(Integer0, IntegerM1)
 
 
 class String(Atom, BoxElementMixin):

mathics/core/convert/expression.py

@@ -99,23 +99,6 @@ def to_numeric_args(mathics_args: Type[BaseElement], evaluation) -> list:
     )
 
 
-def to_numeric_sympy_args(mathics_args: Type[BaseElement], evaluation) -> list:
-    """
-    Convert Mathics arguments, such as the arguments in an evaluation
-    method a Python list that is sutiable for feeding as arguments
-    into SymPy.
-
-    We make use of fast conversions for literals.
-    """
-    if mathics_args.is_literal:
-        sympy_args = [mathics_args.value]
-    else:
-        args = numerify(mathics_args, evaluation).get_sequence()
-        sympy_args = [a.to_sympy() for a in args]
-
-    return sympy_args
-
-
 expression_constructor_map = {
     SymbolList: lambda head, *args, **kwargs: ListExpression(*args, **kwargs)
 }

mathics/core/convert/mpmath.py

@@ -6,25 +6,16 @@
 import mpmath
 import sympy
 
-from mathics.core.atoms import (
-    Complex,
-    Integer0,
-    Integer1,
-    IntegerM1,
-    MachineReal,
-    MachineReal0,
-    PrecisionReal,
-)
+from mathics.core.atoms import Complex, MachineReal, MachineReal0, PrecisionReal
 from mathics.core.element import BaseElement
-from mathics.core.expression import Expression
-from mathics.core.systemsymbols import SymbolDirectedInfinity, SymbolIndeterminate
-
-ExpressionInfinity = Expression(SymbolDirectedInfinity, Integer1)
-ExpressionMInfinity = Expression(SymbolDirectedInfinity, IntegerM1)
-ExpressionIInfinity = Expression(SymbolDirectedInfinity, Complex(Integer0, Integer1))
-ExpressionMIInfinity = Expression(SymbolDirectedInfinity, Complex(Integer0, IntegerM1))
-
-ExpressionComplexInfinity = Expression(SymbolDirectedInfinity)
+from mathics.core.expression import (
+    MATHICS3_COMPLEX_INFINITY,
+    MATHICS3_I_INFINITY,
+    MATHICS3_I_NEG_INFINITY,
+    MATHICS3_INFINITY,
+    MATHICS3_NEG_INFINITY,
+)
+from mathics.core.systemsymbols import SymbolIndeterminate
 
 
 @lru_cache(maxsize=1024)
@@ -41,7 +32,7 @@ def from_mpmath(
         return SymbolIndeterminate
     if isinstance(value, mpmath.mpf):
         if mpmath.isinf(value):
-            return ExpressionInfinity if value > 0 else ExpressionMInfinity
+            return MATHICS3_INFINITY if value > 0 else MATHICS3_NEG_INFINITY
         if precision is None:
             return MachineReal(float(value))
         # If the error if of the order of the number, the number
@@ -56,10 +47,10 @@ def from_mpmath(
         val_re, val_im = value.real, value.imag
         if mpmath.isinf(val_re):
             if mpmath.isinf(val_im):
-                return ExpressionComplexInfinity
-            return ExpressionInfinity if val_re > 0 else ExpressionMInfinity
+                return MATHICS3_COMPLEX_INFINITY
+            return MATHICS3_INFINITY if val_re > 0 else MATHICS3_NEG_INFINITY
         elif mpmath.isinf(val_im):
-            return ExpressionIInfinity if val_im > 0 else ExpressionMIInfinity
+            return MATHICS3_I_INFINITY if val_im > 0 else MATHICS3_I_NEG_INFINITY
         real = from_mpmath(val_re, precision=precision)
         imag = from_mpmath(val_im, precision=precision)
         return Complex(real, imag)