WIP #937 N( Equal-expression ) does not return numeric result

Author: axkr

symja_android_library/matheclipse-core/src/main/java/org/matheclipse/core/builtin/BooleanFunctions.java

@@ -1733,6 +1733,12 @@ public IExpr evaluate(final IAST ast, EvalEngine engine) {
       if (ast.exists(x -> x.equals(S.Undefined))) {
         return S.Undefined;
       }
+
+      IAST evalArgs = engine.evalArgsN(ast, ISymbol.NOATTRIBUTE);
+      if (evalArgs.isPresent()) {
+        return evalArgs;
+      }
+
       if (ast.size() > 2) {
         IExpr.COMPARE_TERNARY b = IExpr.COMPARE_TERNARY.UNDECIDABLE;
         if (ast.isAST2()) {
@@ -2210,6 +2216,11 @@ public IExpr evaluate(IAST ast, EvalEngine engine) {
         return S.True;
       }
 
+      IASTMutable evalArgs = engine.evalArgsN(ast, ISymbol.NOATTRIBUTE);
+      if (evalArgs.isPresent()) {
+        return evalArgs;
+      }
+
       IASTAppendable flattened;
       if ((flattened = EvalAttributes.flattenDeep(ast)).isPresent()) {
         ast = flattened;
@@ -4660,6 +4671,10 @@ private static final class Unequal extends Equal {
 
     @Override
     public IExpr evaluate(final IAST ast, EvalEngine engine) {
+      IASTMutable evalArgs = engine.evalArgsN(ast, ISymbol.NOATTRIBUTE);
+      if (evalArgs.isPresent()) {
+        return evalArgs;
+      }
       if (ast.exists(x -> x.equals(S.Undefined))) {
         return S.Undefined;
       }

symja_android_library/matheclipse-core/src/main/java/org/matheclipse/core/builtin/GraphicsFunctions.java

@@ -7,6 +7,7 @@
 import org.matheclipse.core.convert.RGBColor;
 import org.matheclipse.core.eval.Errors;
 import org.matheclipse.core.eval.EvalEngine;
+import org.matheclipse.core.eval.interfaces.AbstractCoreFunctionEvaluator;
 import org.matheclipse.core.eval.interfaces.AbstractEvaluator;
 import org.matheclipse.core.eval.interfaces.AbstractSymbolEvaluator;
 import org.matheclipse.core.eval.util.OptionArgs;
@@ -660,6 +661,7 @@ private static void init() {
       S.Cylinder.setEvaluator(new Cylinder());
       S.Dodecahedron.setEvaluator(new Dodecahedron());
       S.Icosahedron.setEvaluator(new Icosahedron());
+      S.Labeled.setEvaluator(new Labeled());
       S.Line.setEvaluator(new Line());
       S.Octahedron.setEvaluator(new Octahedron());
       S.Point.setEvaluator(new Point());
@@ -677,6 +679,24 @@ private static void init() {
     }
   }
 
+  private static final class Labeled extends AbstractCoreFunctionEvaluator {
+
+    @Override
+    public IExpr evaluate(final IAST ast, EvalEngine engine) {
+      IASTMutable evalArgs = engine.evalArgsN(ast, ISymbol.NOATTRIBUTE);
+      if (evalArgs.isPresent()) {
+        return evalArgs;
+      }
+      return F.NIL;
+    }
+
+    @Override
+    public int[] expectedArgSize(IAST ast) {
+      return ARGS_2_3;
+    }
+
+  }
+
   private static class Line extends AbstractEvaluator implements IGraphics2D, IGraphics3D {
 
     @Override

symja_android_library/matheclipse-core/src/main/java/org/matheclipse/core/eval/EvalEngine.java

@@ -826,6 +826,22 @@ public void evalArg(final IASTMutable[] result0, final IAST ast, final IExpr arg
 
   }
 
+  /**
+   * Evaluate the arguments of the given <code>ast</code> numerically, if {@link #isNumericMode()}
+   * is <code>true</code> taking the attributes
+   * <code>HoldFirst, NHoldFirst, HoldRest, NHoldRest, NumericFunction</code> into account.
+   *
+   * @param ast
+   * @param attributes
+   * @return <code>F.NIL</code> is no evaluation was possible
+   */
+  public IASTMutable evalArgsN(final IAST ast, final int attributes) {
+    if (isNumericMode()) {
+      return evalArgs(ast, attributes, true);
+    }
+    return F.NIL;
+  }
+
   /**
    * Evaluate the arguments of the given ast, taking the attributes <code>
    * HoldFirst, NHoldFirst, HoldRest, NHoldRest, NumericFunction</code> into account.

symja_android_library/matheclipse-core/src/main/java/org/matheclipse/core/expression/AbstractAST.java

@@ -4044,20 +4044,23 @@ public boolean isNumericFunction(boolean allowList) {
         }
       }
     }
-    if (allowList) {
-      if (head().isSymbol() && ((ISymbol) head()).isNumericFunctionAttribute() || isList()) {
-        // check if all arguments are "numeric"
-        boolean forAll = forAll(x -> x.isNumericFunction(allowList), 1);
-        addEvalFlags(
-            forAll ? IAST.IS_NUMERIC_FUNCTION_OR_LIST : IAST.IS_NOT_NUMERIC_FUNCTION_OR_LIST);
-        return forAll;
-      }
-    } else {
-      if (head().isSymbol() && ((ISymbol) head()).isNumericFunctionAttribute()) {
-        // check if all arguments are "numeric"
-        boolean forAll = forAll(x -> x.isNumericFunction(allowList), 1);
-        addEvalFlags(forAll ? IAST.IS_NUMERIC_FUNCTION : IAST.IS_NOT_NUMERIC_FUNCTION);
-        return forAll;
+    if (head().isSymbol()) {
+      ISymbol header = (ISymbol) head();
+      if (allowList) {
+        if (header.isNumericFunctionAttribute() || isList()) {
+          // check if all arguments are "numeric"
+          boolean forAll = forAll(x -> x.isNumericFunction(allowList), 1);
+          addEvalFlags(
+              forAll ? IAST.IS_NUMERIC_FUNCTION_OR_LIST : IAST.IS_NOT_NUMERIC_FUNCTION_OR_LIST);
+          return forAll;
+        }
+      } else {
+        if (header.isNumericFunctionAttribute()) {
+          // check if all arguments are "numeric"
+          boolean forAll = forAll(x -> x.isNumericFunction(allowList), 1);
+          addEvalFlags(forAll ? IAST.IS_NUMERIC_FUNCTION : IAST.IS_NOT_NUMERIC_FUNCTION);
+          return forAll;
+        }
       }
     }
     return false;

symja_android_library/matheclipse-core/src/main/java/org/matheclipse/core/expression/S.java

@@ -11685,4 +11685,8 @@ public static boolean isDomain(ISymbol domain) {
     return domain == Algebraics || domain == Booleans || domain == Complexes || domain == Integers
         || domain == Primes || domain == Rationals || domain == Reals;
   }
+
+  static {
+    C.setAttributes(ISymbol.NHOLDALL);
+  }
 }

symja_android_library/matheclipse-core/src/test/java/org/matheclipse/core/system/LowercaseTestCase.java

@@ -15979,6 +15979,11 @@ public void testDeterminePrecision() {
 
   @Test
   public void testN() {
+    // issue #937
+    check("(x==-157079632679/100000000000) // N", //
+        "x==-1.5708");
+    check("ConditionalExpression(x==-157079632679/100000000000*C(1),C(1)∈Integers) // N", //
+        "ConditionalExpression(x==-1.5708*C(1),C(1)∈Integers)");
     check("N({Labeled(4/3,\"test\")})", //
         "{Labeled(1.33333,test)}");
     check("N(Labeled(4/3,\"test\"))", //