Refactor/Clean up

- renamed Algebra.getNumeratorDenominator -> numeratorDenominator

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

@@ -2139,7 +2139,7 @@ private static IExpr factor(IAST ast, IExpr arg1, VariablesSet eVar, boolean squ
       if (!arg1.isTimes() && !arg1.isPower()) {
         expr = S.Together.of(engine, arg1);
         if (expr.isAST()) {
-          IExpr[] parts = Algebra.getNumeratorDenominator((IAST) expr, engine, true);
+          IExpr[] parts = Algebra.numeratorDenominator((IAST) expr, true, engine);
           if (!parts[1].isOne()) {
             try {
               IExpr numerator = factorExpr(F.Factor(parts[0]), parts[0], eVar, squareFree,
@@ -2296,7 +2296,7 @@ public static IExpr evaluateSolve(IExpr expr, SolveData solveData, EvalEngine en
         IExpr variable = eVar.getArrayList().get(0);
         expr = S.Together.of(engine, expr);
         if (expr.isAST()) {
-          IExpr[] parts = Algebra.getNumeratorDenominator((IAST) expr, engine, true);
+          IExpr[] parts = Algebra.numeratorDenominator((IAST) expr, true, engine);
           try {
             IExpr numerator =
                 factorExprSolve(F.Factor(parts[0]), parts[0], variable, solveData, engine);
@@ -5309,41 +5309,80 @@ private static IRational factorTermsGCD(IAST plusAST, EvalEngine engine) {
   }
 
   /**
-   * Split the expression into numerator and denominator parts, by calling the <code>Numerator[]
-   * </code> and <code>Denominator[]</code> functions
+   * Split the {@link IAST} expression into numerator and denominator parts, by calling the
+   * <code>Numerator(ast)</code> and <code>Denominator(ast)</code> functions and return the result
+   * at index <code>0</code> (numerator) and index <code>1</code> (denominator).
    *
    * @param ast
-   * @param together TODO
-   * @return an array with the numerator, denominator and the evaluated <code>Together[expr]</code>.
+   * @param together if <code>true</code> the evaluated <code>Together(ast)</code> result, will be
+   *        appended at index <code>2</code> in the result array
+   * @return an array with the numerator, denominator and the evaluated <code>Together(ast)</code>
+   *         if requested.
    */
-  public static IExpr[] getNumeratorDenominator(IAST ast, EvalEngine engine, boolean together) {
+  public static IExpr[] numeratorDenominator(IAST ast, boolean together, EvalEngine engine) {
+    // if (together) {
+    // boolean noSimplifyMode = engine.isNoSimplifyMode();
+    // try {
+    // engine.setNoSimplifyMode(true);
+    // IExpr[] result = new IExpr[3];
+    // result[2] = together(ast, engine);
+    // // split expr into numerator and denominator
+    // result[1] = engine.evaluate(F.Denominator(result[2]));
+    // if (!result[1].isOne()) {
+    // // search roots for the numerator expression
+    // result[0] = engine.evaluate(F.Numerator(result[2]));
+    // } else {
+    // result[0] = ast; // result[2];
+    // }
+    // return result;
+    // } finally {
+    // engine.setNoSimplifyMode(noSimplifyMode);
+    // }
+    // }
+    //
+    // IExpr[] result = new IExpr[2];
+    // // split expr into numerator and denominator
+    // result[1] = engine.evaluate(F.Denominator(ast));
+    // if (!result[1].isOne()) {
+    // result[0] = engine.evaluate(F.Numerator(ast));
+    // } else {
+    // result[0] = ast;
+    // }
+    // return result;
+
     if (together) {
       boolean noSimplifyMode = engine.isNoSimplifyMode();
       try {
         engine.setNoSimplifyMode(true);
         IExpr[] result = new IExpr[3];
         result[2] = together(ast, engine);
-        // split expr into numerator and denominator
-        result[1] = engine.evaluate(F.Denominator(result[2]));
-        if (!result[1].isOne()) {
-          // search roots for the numerator expression
-          result[0] = engine.evaluate(F.Numerator(result[2]));
-        } else {
-          result[0] = ast; // result[2];
-        }
-        return result;
+        return splitNumeratorDenominator(ast, result[2], result, engine);
       } finally {
         engine.setNoSimplifyMode(noSimplifyMode);
       }
     }
 
     IExpr[] result = new IExpr[2];
-    // split expr into numerator and denominator
-    result[1] = engine.evaluate(F.Denominator(ast));
+    return splitNumeratorDenominator(ast, ast, result, engine);
+  }
+
+  /**
+   * Split <code>rewrittenAST</code> into numerator and denominator.
+   * 
+   * @param originalAST the original {@link IAST} expression
+   * @param rewrittenAST the rewritten AST (for example by {@link S#Together}
+   * @param result the allocated result array
+   * @param engine the evaluation engine
+   * 
+   * @return the <code>result</code> array of expressions <code>[numerator, denominator]</code>.
+   */
+  private static IExpr[] splitNumeratorDenominator(final IAST originalAST, final IExpr rewrittenAST,
+      IExpr[] result, EvalEngine engine) {
+    result[1] = engine.evaluate(F.Denominator(rewrittenAST));
     if (!result[1].isOne()) {
-      result[0] = engine.evaluate(F.Numerator(ast));
+      result[0] = engine.evaluate(F.Numerator(rewrittenAST));
     } else {
-      result[0] = ast;
+      result[0] = originalAST;
     }
     return result;
   }

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

@@ -280,7 +280,6 @@ public IExpr evaluate(final IAST ast, EvalEngine engine) {
           return assoc;
         } catch (ValidateException ve) {
           Errors.printMessage(S.Association, ve, engine);
-          // print no message
         }
         return evaled ? assocList : F.NIL;
       }

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

@@ -415,7 +415,7 @@ private IExpr tryTransformations(IExpr expr) {
           if (fFullSimplify) {
             if (together.isTimes()) {
               IExpr[] parts =
-                  Algebra.getNumeratorDenominator((IAST) together, EvalEngine.get(), true);
+                  Algebra.numeratorDenominator((IAST) together, true, EvalEngine.get());
               IExpr numerator = parts[0];
               IExpr denominator = parts[1];
               // common factors in numerator, denominator may be canceled here, so check if we have

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

@@ -734,7 +734,7 @@ public int simplifyAndAnalyze() {
   }
 
   public void splitNumeratorDenominator(IAST ast) {
-    IExpr[] result = Algebra.getNumeratorDenominator(ast, fEngine, true);
+    IExpr[] result = Algebra.numeratorDenominator(ast, true, fEngine);
     this.fNumerator = result[0];
     this.fDenominator = result[1];
     this.fExpr = result[2];

symja_android_library/matheclipse-core/src/main/java/org/matheclipse/core/reflection/system/Eliminate.java

@@ -448,7 +448,7 @@ private static IExpr extractVariableRecursive(IExpr exprWithVariable, IExpr expr
           IAST timesWithoutVariable = timesFilter[0];
           IAST timesWithVariable = timesFilter[1];
           if (timesWithoutVariable.isAST0()) {
-            IExpr[] numerDenom = Algebra.getNumeratorDenominator(ast, EvalEngine.get(), true);
+            IExpr[] numerDenom = Algebra.numeratorDenominator(ast, true, EvalEngine.get());
             if (!numerDenom[1].isOne()) {
               IExpr[] numerLinear = numerDenom[0].linear(variable);
               if (numerLinear != null) {

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

@@ -24339,6 +24339,10 @@ public void testTimeValue() {
   }
 
   public void testTogether() {
+    check("Together((1/x-1/3)/(x-3)^2)", //
+        "1/(3*(3-x)*x)");
+    check("Together((1/x-1/3)^3/(x-3))", //
+        "-(3-x)^2/(27*x^3)");
     check("Together((1/x-1/3)^3/(x-3)^2)", //
         "(3-x)/(27*x^3)");
     check("Together((1/x-1/3)/(x-3))", //

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

@@ -346,6 +346,9 @@ public void testSolveInequality() {
   }
 
   public void testSolve() {
+    check("Solve(3*(x+a)*(x-b)==0,x)", //
+        "{{x->-a},{x->b}}");
+
     // github #261 - JUnit test for Apfloat switching to complex Power calculation
     check("Solve(0.00004244131815783 == x^5 , x)", //
         "{{x->-0.10802279680851234+I*0.07848315587546605},{x->-0.10802279680851212+I*(-0.07848315587546605)},"//