diff --git a/symja_android_library/matheclipse-core/src/main/java/org/matheclipse/core/patternmatching/IPatternMap.java b/symja_android_library/matheclipse-core/src/main/java/org/matheclipse/core/patternmatching/IPatternMap.java
index c5dc0bd092..156f8dea55 100644
--- a/symja_android_library/matheclipse-core/src/main/java/org/matheclipse/core/patternmatching/IPatternMap.java
+++ b/symja_android_library/matheclipse-core/src/main/java/org/matheclipse/core/patternmatching/IPatternMap.java
@@ -1625,42 +1625,8 @@ static IPatternMap determinePatterns(final IExpr lhsPatternExpr, int[] priority,
 
       determinePatternsRecursive(patternIndexMap, (IAST) lhsPatternExpr, priority,
           ruleWithoutPattern, 1);
-      int size = patternIndexMap.size();
-      switch (size) {
-        case 1:
-          PatternMap1 patternMap1 = new PatternMap1();
-          patternMap1.fSymbol1 = patternIndexMap.get(0).getFirst();
-          patternMap1.fPatternObject1 = patternIndexMap.get(0).getSecond();
-          return patternMap1;
-        case 2:
-          PatternMap2 patternMap2 = new PatternMap2();
-          patternMap2.fSymbol1 = patternIndexMap.get(0).getFirst();
-          patternMap2.fPatternObject1 = patternIndexMap.get(0).getSecond();
-          patternMap2.fSymbol2 = patternIndexMap.get(1).getFirst();
-          patternMap2.fPatternObject2 = patternIndexMap.get(1).getSecond();
-          return patternMap2;
-        case 3:
-          PatternMap3 patternMap3 = new PatternMap3();
-          patternMap3.fSymbol1 = patternIndexMap.get(0).getFirst();
-          patternMap3.fPatternObject1 = patternIndexMap.get(0).getSecond();
-          patternMap3.fSymbol2 = patternIndexMap.get(1).getFirst();
-          patternMap3.fPatternObject2 = patternIndexMap.get(1).getSecond();
-          patternMap3.fSymbol3 = patternIndexMap.get(2).getFirst();
-          patternMap3.fPatternObject3 = patternIndexMap.get(2).getSecond();
-          return patternMap3;
-      }
-      PatternMap patternMap = new PatternMap();
-      patternMap.fRuleWithoutPattern = ruleWithoutPattern[0];
-      patternMap.fSymbolsOrPattern = new IExpr[size];
-      patternMap.fSymbolsOrPatternValues = new IExpr[size];
-      patternMap.fPatternObjects = new IPatternObject[size];
-      int i = 0;
-      for (GenericPair<IExpr, IPatternObject> entry : patternIndexMap) {
-        patternMap.fSymbolsOrPattern[i] = entry.getFirst();
-        patternMap.fPatternObjects[i] = entry.getSecond();
-        i++;
-      }
-      return patternMap;
+      boolean isRuleWithoutPattern = ruleWithoutPattern[0];
+      return createPatternMap(patternIndexMap, isRuleWithoutPattern);
     } else if (lhsPatternExpr instanceof PatternNested) {
       PatternNested pattern2 = (PatternNested) lhsPatternExpr;
       // PatternMap1 patternMap1 = new PatternMap1();
@@ -1691,6 +1657,87 @@ static IPatternMap determinePatterns(final IExpr lhsPatternExpr, int[] priority,
     return new PatternMap0();
   }
 
+  public static IPatternMap createSymbolValue(
+      List<GenericPair<IExpr, ISymbol>> patternIndexMap) {
+    int size = patternIndexMap.size();
+    switch (size) {
+      case 1:
+        PatternMap1 patternMap1 = new PatternMap1();
+        patternMap1.fValue1 = patternIndexMap.get(0).getFirst();
+        patternMap1.fSymbol1 = patternIndexMap.get(0).getSecond();
+        return patternMap1;
+      case 2:
+        PatternMap2 patternMap2 = new PatternMap2();
+        patternMap2.fValue1 = patternIndexMap.get(0).getFirst();
+        patternMap2.fSymbol1 = patternIndexMap.get(0).getSecond();
+        patternMap2.fValue2 = patternIndexMap.get(1).getFirst();
+        patternMap2.fSymbol2 = patternIndexMap.get(1).getSecond();
+        return patternMap2;
+      case 3:
+        PatternMap3 patternMap3 = new PatternMap3();
+        patternMap3.fValue1 = patternIndexMap.get(0).getFirst();
+        patternMap3.fSymbol1 = patternIndexMap.get(0).getSecond();
+        patternMap3.fValue2 = patternIndexMap.get(1).getFirst();
+        patternMap3.fSymbol2 = patternIndexMap.get(1).getSecond();
+        patternMap3.fValue3 = patternIndexMap.get(2).getFirst();
+        patternMap3.fSymbol3 = patternIndexMap.get(2).getSecond();
+        return patternMap3;
+    }
+    PatternMap patternMap = new PatternMap();
+    patternMap.fRuleWithoutPattern = true;
+    patternMap.fSymbolsOrPattern = new IExpr[size];
+    patternMap.fSymbolsOrPatternValues = new IExpr[size];
+    patternMap.fPatternObjects = new IPatternObject[size];
+    int i = 0;
+    for (GenericPair<IExpr, ISymbol> entry : patternIndexMap) {
+      patternMap.fSymbolsOrPatternValues[i] = entry.getFirst();
+      patternMap.fSymbolsOrPattern[i] = entry.getSecond();
+      i++;
+    }
+    return patternMap;
+  }
+
+  public static IPatternMap createPatternMap(
+      List<GenericPair<IExpr, IPatternObject>> patternIndexMap,
+      boolean isRuleWithoutPattern) {
+    int size = patternIndexMap.size();
+    switch (size) {
+      case 1:
+        PatternMap1 patternMap1 = new PatternMap1();
+        patternMap1.fSymbol1 = patternIndexMap.get(0).getFirst();
+        patternMap1.fPatternObject1 = patternIndexMap.get(0).getSecond();
+        return patternMap1;
+      case 2:
+        PatternMap2 patternMap2 = new PatternMap2();
+        patternMap2.fSymbol1 = patternIndexMap.get(0).getFirst();
+        patternMap2.fPatternObject1 = patternIndexMap.get(0).getSecond();
+        patternMap2.fSymbol2 = patternIndexMap.get(1).getFirst();
+        patternMap2.fPatternObject2 = patternIndexMap.get(1).getSecond();
+        return patternMap2;
+      case 3:
+        PatternMap3 patternMap3 = new PatternMap3();
+        patternMap3.fSymbol1 = patternIndexMap.get(0).getFirst();
+        patternMap3.fPatternObject1 = patternIndexMap.get(0).getSecond();
+        patternMap3.fSymbol2 = patternIndexMap.get(1).getFirst();
+        patternMap3.fPatternObject2 = patternIndexMap.get(1).getSecond();
+        patternMap3.fSymbol3 = patternIndexMap.get(2).getFirst();
+        patternMap3.fPatternObject3 = patternIndexMap.get(2).getSecond();
+        return patternMap3;
+    }
+    PatternMap patternMap = new PatternMap();
+    patternMap.fRuleWithoutPattern = isRuleWithoutPattern;
+    patternMap.fSymbolsOrPattern = new IExpr[size];
+    patternMap.fSymbolsOrPatternValues = new IExpr[size];
+    patternMap.fPatternObjects = new IPatternObject[size];
+    int i = 0;
+    for (GenericPair<IExpr, IPatternObject> entry : patternIndexMap) {
+      patternMap.fSymbolsOrPattern[i] = entry.getFirst();
+      patternMap.fPatternObjects[i] = entry.getSecond();
+      i++;
+    }
+    return patternMap;
+  }
+
   /**
    * Determine all patterns (i.e. all objects of instance IPattern) in the given expression
    *
diff --git a/symja_android_library/matheclipse-core/src/main/java/org/matheclipse/core/patternmatching/PatternMatcherAndEvaluator.java b/symja_android_library/matheclipse-core/src/main/java/org/matheclipse/core/patternmatching/PatternMatcherAndEvaluator.java
index a7b71df724..d9cdba5980 100644
--- a/symja_android_library/matheclipse-core/src/main/java/org/matheclipse/core/patternmatching/PatternMatcherAndEvaluator.java
+++ b/symja_android_library/matheclipse-core/src/main/java/org/matheclipse/core/patternmatching/PatternMatcherAndEvaluator.java
@@ -4,12 +4,14 @@
 import java.io.IOException;
 import java.io.ObjectInput;
 import java.io.ObjectOutput;
+import java.util.List;
 import org.matheclipse.core.basic.Config;
 import org.matheclipse.core.eval.EvalEngine;
 import org.matheclipse.core.eval.exception.ConditionException;
 import org.matheclipse.core.eval.exception.ReturnException;
 import org.matheclipse.core.expression.F;
 import org.matheclipse.core.expression.S;
+import org.matheclipse.core.generic.GenericPair;
 import org.matheclipse.core.interfaces.IAST;
 import org.matheclipse.core.interfaces.IEvalStepListener;
 import org.matheclipse.core.interfaces.IExpr;
@@ -216,6 +218,16 @@ public IExpr eval(final IExpr leftHandSide, EvalEngine engine) {
     return replace(leftHandSide, engine, true);
   }
 
+  public static IExpr evalInternal(final IExpr leftHandSide, final IExpr rightHandSide,
+      List<GenericPair<IExpr, ISymbol>> patternIndexMap) {
+    PatternMatcherAndEvaluator pm = new PatternMatcherAndEvaluator();
+    IPatternMap patternMap = IPatternMap.createSymbolValue(patternIndexMap);
+    pm.fPatternMap = patternMap;
+    pm.fRightHandSide = rightHandSide;
+    pm.setLHSExprToMatch(leftHandSide);
+    return pm.replacePatternMatch(leftHandSide, patternMap, EvalEngine.get(), true);
+  }
+
   public IExpr replace(final IExpr leftHandSide, EvalEngine engine, boolean evaluate) {
     IPatternMap patternMap = null;
     if (isRuleWithoutPatterns()) {
@@ -288,7 +300,9 @@ public IExpr replacePatternMatch(final IExpr leftHandSide, IPatternMap patternMa
 
     engine.pushOptionsStack();
     try {
-      engine.setOptionsPattern(fLhsPatternExpr.topHead(), patternMap);
+      if (fLhsPatternExpr != null) {
+        engine.setOptionsPattern(fLhsPatternExpr.topHead(), patternMap);
+      }
       if (fRightHandSide == DUMMY_SUBSET_CASES) {
         fSubstitutedMatch = patternMap.substitutePatterns(fLhsPatternExpr, F.CEmptySequence);
       } else {
diff --git a/symja_android_library/matheclipse-core/src/main/java/org/matheclipse/core/patternmatching/RulesData.java b/symja_android_library/matheclipse-core/src/main/java/org/matheclipse/core/patternmatching/RulesData.java
index a3727589ea..d61b3b6e6a 100644
--- a/symja_android_library/matheclipse-core/src/main/java/org/matheclipse/core/patternmatching/RulesData.java
+++ b/symja_android_library/matheclipse-core/src/main/java/org/matheclipse/core/patternmatching/RulesData.java
@@ -574,7 +574,7 @@ public final IPatternMatcher putDownRule(final IExpr leftHandSide, final IExpr r
 
   public final IPatternMatcher putDownRule(final int setSymbol, final boolean equalRule,
       final IExpr leftHandSide, final IExpr rightHandSide) {
-    return putDownRule(IPatternMatcher.SET_DELAYED, false, leftHandSide, rightHandSide,
+    return putDownRule(setSymbol, false, leftHandSide, rightHandSide,
         IPatternMap.DEFAULT_RULE_PRIORITY);
   }