add stop on node

src/main/java/org/nwapw/abacus/Abacus.java

@@ -1,7 +1,6 @@
 package org.nwapw.abacus;
 
 import org.nwapw.abacus.config.ConfigurationObject;
-import org.nwapw.abacus.fx.AbacusApplication;
 import org.nwapw.abacus.number.NaiveNumber;
 import org.nwapw.abacus.number.NumberInterface;
 import org.nwapw.abacus.parsing.LexerTokenizer;
@@ -12,7 +11,9 @@ import org.nwapw.abacus.plugin.PluginManager;
 import org.nwapw.abacus.plugin.StandardPlugin;
 import org.nwapw.abacus.tree.NumberReducer;
 import org.nwapw.abacus.tree.TreeNode;
+import org.nwapw.abacus.window.Window;
 
+import javax.swing.*;
 import java.io.File;
 import java.io.IOException;
 import java.lang.reflect.InvocationTargetException;
@@ -52,7 +53,10 @@ public class Abacus {
      * from a string.
      */
     private TreeBuilder treeBuilder;
-
+    private Window window;
+    public boolean getStop(){
+        return window.getStop();
+    }
     /**
      * Creates a new instance of the Abacus calculator.
      */
@@ -78,7 +82,13 @@ public class Abacus {
     }
 
     public static void main(String[] args) {
-        AbacusApplication.launch(AbacusApplication.class, args);
+        try {
+            UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
+        } catch (ClassNotFoundException | InstantiationException | UnsupportedLookAndFeelException | IllegalAccessException e) {
+            e.printStackTrace();
+        }
+
+        new Window(new Abacus()).setVisible(true);
     }
 
     /**
@@ -126,7 +136,7 @@ public class Abacus {
      * @return the resulting tree, null if the tree builder or the produced tree are null.
      */
     public TreeNode parseString(String input) {
-        return treeBuilder.fromString(input);
+        return treeBuilder.fromString(input,this);
     }
 
     /**
@@ -158,4 +168,8 @@ public class Abacus {
         }
         return null;
     }
+
+    public void setWindow(Window window) {
+        this.window = window;
+    }
 }

src/main/java/org/nwapw/abacus/fx/AbacusApplication.java

@@ -1,24 +0,0 @@
-package org.nwapw.abacus.fx;
-
-import javafx.application.Application;
-import javafx.fxml.FXMLLoader;
-import javafx.scene.Parent;
-import javafx.scene.Scene;
-import javafx.stage.Stage;
-
-/**
- * The main application class for JavaFX responsible for loading
- * and displaying the fxml file.
- */
-public class AbacusApplication extends Application {
-
-    @Override
-    public void start(Stage primaryStage) throws Exception {
-        Parent parent = FXMLLoader.load(getClass().getResource("/abacus.fxml"));
-        Scene mainScene = new Scene(parent, 320, 480);
-        primaryStage.setScene(mainScene);
-        primaryStage.setTitle("Abacus");
-        primaryStage.show();
-    }
-
-}

src/main/java/org/nwapw/abacus/fx/AbacusController.java

@@ -1,94 +0,0 @@
-package org.nwapw.abacus.fx;
-
-import javafx.collections.FXCollections;
-import javafx.collections.ObservableList;
-import javafx.fxml.FXML;
-import javafx.scene.control.*;
-import javafx.scene.text.Text;
-import javafx.util.Callback;
-import org.nwapw.abacus.Abacus;
-import org.nwapw.abacus.number.NumberInterface;
-import org.nwapw.abacus.tree.TreeNode;
-
-
-/**
- * The controller for the abacus FX UI, responsible
- * for all the user interaction.
- */
-public class AbacusController {
-
-    /**
-     * Constant string that is displayed if the text could not be lexed or parsed.
-     */
-    private static final String ERR_SYNTAX = "Syntax Error";
-    /**
-     * Constant string that is displayed if the tree could not be reduced.
-     */
-    private static final String ERR_EVAL = "Evaluation Error";
-
-    @FXML
-    private TableView<HistoryModel> historyTable;
-    @FXML
-    private TableColumn<HistoryModel, String> inputColumn;
-    @FXML
-    private TableColumn<HistoryModel, String> parsedColumn;
-    @FXML
-    private TableColumn<HistoryModel, String> outputColumn;
-    @FXML
-    private Text outputText;
-    @FXML
-    private TextField inputField;
-    @FXML
-    private Button inputButton;
-
-    /**
-     * The list of history entries, created by the users.
-     */
-    private ObservableList<HistoryModel> historyData;
-
-    /**
-     * The abacus instance used for calculations and all
-     * other main processing code.
-     */
-    private Abacus abacus;
-
-    @FXML
-    public void initialize(){
-        Callback<TableColumn<HistoryModel, String>, TableCell<HistoryModel, String>> cellFactory =
-                param -> new CopyableCell<>();
-
-        abacus = new Abacus();
-        historyData = FXCollections.observableArrayList();
-        historyTable.setItems(historyData);
-        historyTable.getSelectionModel().setCellSelectionEnabled(true);
-        inputColumn.setCellFactory(cellFactory);
-        inputColumn.setCellValueFactory(cell -> cell.getValue().inputProperty());
-        parsedColumn.setCellFactory(cellFactory);
-        parsedColumn.setCellValueFactory(cell -> cell.getValue().parsedProperty());
-        outputColumn.setCellFactory(cellFactory);
-        outputColumn.setCellValueFactory(cell -> cell.getValue().outputProperty());
-    }
-
-    @FXML
-    private void performCalculation(){
-        inputButton.setDisable(true);
-        TreeNode constructedTree = abacus.parseString(inputField.getText());
-        if(constructedTree == null){
-            outputText.setText(ERR_SYNTAX);
-            inputButton.setDisable(false);
-            return;
-        }
-        NumberInterface evaluatedNumber = abacus.evaluateTree(constructedTree);
-        if(evaluatedNumber == null){
-            outputText.setText(ERR_EVAL);
-            inputButton.setDisable(false);
-            return;
-        }
-        outputText.setText(evaluatedNumber.toString());
-        historyData.add(new HistoryModel(inputField.getText(), constructedTree.toString(), evaluatedNumber.toString()));
-
-        inputButton.setDisable(false);
-        inputField.setText("");
-    }
-
-}

src/main/java/org/nwapw/abacus/fx/CopyableCell.java

@@ -1,35 +0,0 @@
-package org.nwapw.abacus.fx;
-
-import javafx.scene.control.TableCell;
-import javafx.scene.input.MouseEvent;
-
-import java.awt.*;
-import java.awt.datatransfer.StringSelection;
-
-/**
- * A cell that copies its value to the clipboard
- * when double clicked.
- * @param <S> The type of the table view generic type.
- * @param <T> The type of the value contained in the cell.
- */
-public class CopyableCell<S, T> extends TableCell<S, T> {
-
-    /**
-     * Creates a new copyable cell.
-     */
-    public CopyableCell(){
-        addEventFilter(MouseEvent.MOUSE_CLICKED, event -> {
-            if(event.getClickCount() == 2){
-                Toolkit.getDefaultToolkit().getSystemClipboard()
-                        .setContents(new StringSelection(getText()), null);
-            }
-        });
-    }
-
-    @Override
-    protected void updateItem(T item, boolean empty) {
-        super.updateItem(item, empty);
-        setText((empty || item == null) ? null : item.toString());
-        setGraphic(null);
-    }
-}

src/main/java/org/nwapw/abacus/fx/HistoryModel.java

@@ -1,87 +0,0 @@
-package org.nwapw.abacus.fx;
-
-import javafx.beans.property.SimpleStringProperty;
-import javafx.beans.property.StringProperty;
-
-/**
- * The data model used for storing history entries.
- */
-public class HistoryModel {
-
-    /**
-     * The property used for displaying the column
-     * for the user input.
-     */
-    private final StringProperty input;
-    /**
-     * The property used for displaying the column
-     * that contains the parsed input.
-     */
-    private final StringProperty parsed;
-    /**
-     * The property used for displaying the column
-     * that contains the program output.
-     */
-    private final StringProperty output;
-
-    /**
-     * Creates a new history model with the given variables.
-     * @param input the user input
-     * @param parsed the parsed input
-     * @param output the program output.
-     */
-    public HistoryModel(String input, String parsed, String output){
-        this.input = new SimpleStringProperty();
-        this.parsed = new SimpleStringProperty();
-        this.output = new SimpleStringProperty();
-        this.input.setValue(input);
-        this.parsed.setValue(parsed);
-        this.output.setValue(output);
-    }
-
-    /**
-     * Gets the input property.
-     * @return the input property.
-     */
-    public StringProperty inputProperty() {
-        return input;
-    }
-    /**
-     * Gets the input.
-     * @return the input.
-     */
-    public String getInput() {
-        return input.get();
-    }
-
-    /**
-     * Gets the parsed input property.
-     * @return the parsed input property.
-     */
-    public StringProperty parsedProperty() {
-        return parsed;
-    }
-    /**
-     * Gets the parsed input.
-     * @return the parsed input.
-     */
-    public String getParsed() {
-        return parsed.get();
-    }
-
-    /**
-     * Gets the output property.
-     * @return the output property.
-     */
-    public StringProperty outputProperty() {
-        return output;
-    }
-    /**
-     * Gets the program output.
-     * @return the output.
-     */
-    public String getOutput() {
-        return output.get();
-    }
-
-}

src/main/java/org/nwapw/abacus/number/BinaryNumber.java

@@ -1,162 +0,0 @@
-package org.nwapw.abacus.number;
-
-public class BinaryNumber implements NumberInterface{
-
-    /**
-     * The number zero.
-     */
-    public static final BinaryNumber ZERO = new BinaryNumber(0);
-    /**
-     * The number one.
-     */
-    public static final BinaryNumber ONE = new BinaryNumber(1);
-    /**
-     * The value of this number.
-     */
-    private double value;
-
-    /**
-     * Creates a new BinaryNumber with the given string.
-     *
-     * @param value the value, which will be parsed as a double.
-     */
-    public BinaryNumber(String value) {
-        toStandard(value);
-    }
-    /**
-     * 
-     */
-    private void toStandard(String value) {
-        String before;
-        String after = "";
-        if(value.indexOf(".")==-1){
-            before=value;
-        }else{
-            before = value.substring(0,value.indexOf("."));
-            after = value.substring(value.indexOf(".")+1);
-        }
-        double sum = 0;
-        for(int it=0;before.length()>0;it++){
-            if(before.charAt(before.length()-1)=='1'){
-                sum+=Math.pow(2,it);
-            }
-            if(before.length()>1) {
-                before = before.substring(0, before.length()-1);
-            }else{
-                before = "";
-            }
-        }
-        for(int it=-1;after.length()>0;it--) {
-            if (after.charAt(0) == '1') {
-                sum += Math.pow(2, it);
-            }
-            if (after.length() > 1) {
-                after = after.substring(1);
-            } else {
-                after = "";
-            }
-        }
-
-        this.value = sum;
-    }
-    
-    /**
-     * Creates a new BinaryNumber with the given value.
-     *
-     * @param value the value to use.
-     */
-    public BinaryNumber(double value) {
-        toStandard(""+value);
-    }
-
-    @Override
-    public int getMaxPrecision() {
-        return 18;
-    }
-
-    @Override
-    public NumberInterface multiply(NumberInterface multiplier) {
-        return new BinaryNumber(value * ((BinaryNumber) multiplier).value);
-    }
-
-    @Override
-    public NumberInterface divide(NumberInterface divisor) {
-        return new BinaryNumber(value / ((BinaryNumber) divisor).value);
-    }
-
-    @Override
-    public NumberInterface add(NumberInterface summand) {
-        return new BinaryNumber(value + ((BinaryNumber) summand).value);
-    }
-
-    @Override
-    public NumberInterface subtract(NumberInterface subtrahend) {
-        return new BinaryNumber(value - ((BinaryNumber) subtrahend).value);
-    }
-
-    @Override
-    public NumberInterface negate() {
-        return new BinaryNumber(-value);
-    }
-
-    @Override
-    public NumberInterface intPow(int exponent) {
-        if (exponent == 0) {
-            return BinaryNumber.ONE;
-        }
-        boolean takeReciprocal = exponent < 0;
-        exponent = Math.abs(exponent);
-        NumberInterface power = this;
-        for (int currentExponent = 1; currentExponent < exponent; currentExponent++) {
-            power = power.multiply(this);
-        }
-        if (takeReciprocal) {
-            power = BinaryNumber.ONE.divide(power);
-        }
-        return power;
-    }
-
-    @Override
-    public int compareTo(NumberInterface number) {
-        BinaryNumber num = (BinaryNumber) number;
-        return Double.compare(value, num.value);
-    }
-
-    @Override
-    public int signum() {
-        return this.compareTo(ZERO);
-    }
-
-    @Override
-    public NumberInterface promoteTo(Class<? extends NumberInterface> toClass) {
-        if (toClass == this.getClass()) return this;
-        else if (toClass == PreciseNumber.class) {
-            return new PreciseNumber(Double.toString(value));
-        }
-        return null;
-    }
-
-    public String toString() {
-        double sum = 0;
-        double tempValue = Math.floor(value);
-        double fraction = value-tempValue;
-        for (int it=0;tempValue > 0;it++) {
-
-            if (tempValue % 2 == 1) {
-                sum+=Math.pow(10,it);
-                tempValue-=1;
-            }
-            tempValue=tempValue/2;
-        }
-        for (int it=0;fraction > 0;it--) {
-
-            if (fraction % 2 >= 1) {
-                sum+=Math.pow(10,it);
-                fraction-=1;
-            }
-            fraction=fraction*2;
-        }
-        double shiftBy = Math.pow(10, 10);
-        return Double.toString(Math.round(sum * shiftBy) / shiftBy);
-    }
-}

src/main/java/org/nwapw/abacus/number/NaiveNumber.java

@@ -93,11 +93,6 @@ public class NaiveNumber implements NumberInterface {
         return this.compareTo(ZERO);
     }
 
-    @Override
-    public int ceiling() {
-        return (int) Math.ceil(value);
-    }
-
     @Override
     public NumberInterface promoteTo(Class<? extends NumberInterface> toClass) {
         if (toClass == this.getClass()) return this;

src/main/java/org/nwapw/abacus/number/NumberInterface.java

@@ -79,12 +79,6 @@ public interface NumberInterface {
      */
     int signum();
 
-    /**
-     * Returns the least integer greater than or equal to the number.
-     * @return the least integer >= the number, if int can hold the value.
-     */
-    int ceiling();
-
     /**
      * Promotes this class to another number class.
      *

src/main/java/org/nwapw/abacus/number/PreciseNumber.java

@@ -3,10 +3,6 @@ package org.nwapw.abacus.number;
 import java.math.BigDecimal;
 import java.math.RoundingMode;
 
-/**
- * A number that uses a BigDecimal to store its value,
- * leading to infinite possible precision.
- */
 public class PreciseNumber implements NumberInterface {
 
     /**
@@ -48,12 +44,12 @@ public class PreciseNumber implements NumberInterface {
 
     @Override
     public int getMaxPrecision() {
-        return 65;
+        return 54;
     }
 
     @Override
     public NumberInterface multiply(NumberInterface multiplier) {
-        return new PreciseNumber(this.value.multiply(((PreciseNumber) multiplier).value));
+        return new PreciseNumber(value.multiply(((PreciseNumber) multiplier).value));
     }
 
     @Override
@@ -98,11 +94,6 @@ public class PreciseNumber implements NumberInterface {
         return value.signum();
     }
 
-    @Override
-    public int ceiling() {
-        return (int) Math.ceil(value.doubleValue());
-    }
-
     @Override
     public NumberInterface negate() {
         return new PreciseNumber(value.negate());
@@ -118,7 +109,7 @@ public class PreciseNumber implements NumberInterface {
 
     @Override
     public String toString() {
-        BigDecimal rounded = value.setScale(getMaxPrecision() - 15, RoundingMode.HALF_UP);
+        BigDecimal rounded = value.setScale(getMaxPrecision() - 4, RoundingMode.HALF_UP);
         return rounded.stripTrailingZeros().toPlainString();
     }
 }

src/main/java/org/nwapw/abacus/parsing/Parser.java

@@ -1,5 +1,6 @@
 package org.nwapw.abacus.parsing;
 
+import org.nwapw.abacus.Abacus;
 import org.nwapw.abacus.tree.TreeNode;
 
 import java.util.List;
@@ -18,5 +19,5 @@ public interface Parser<T> {
      * @param tokens the tokens to construct a tree from.
      * @return the constructed tree, or null on error.
      */
-    public TreeNode constructTree(List<T> tokens);
+    public TreeNode constructTree(List<T> tokens,Abacus trace);
 }

src/main/java/org/nwapw/abacus/parsing/ShuntingYardParser.java

@@ -34,6 +34,8 @@ public class ShuntingYardParser implements Parser<Match<TokenType>>, PluginListe
      */
     private Map<String, OperatorType> typeMap;
 
+    //private Abacus trace;
+
     /**
      * Creates a new Shunting Yard parser with the given Abacus instance.
      *
@@ -116,7 +118,8 @@ public class ShuntingYardParser implements Parser<Match<TokenType>>, PluginListe
      * @param matches the list of tokens from the source string.
      * @return the construct tree expression.
      */
-    public TreeNode constructRecursive(List<Match<TokenType>> matches) {
+    public TreeNode constructRecursive(List<Match<TokenType>> matches,Abacus trace) {
+        //this.trace = trace;
         if (matches.size() == 0) return null;
         Match<TokenType> match = matches.remove(0);
         TokenType matchType = match.getType();
@@ -124,22 +127,22 @@ public class ShuntingYardParser implements Parser<Match<TokenType>>, PluginListe
             String operator = match.getContent();
             OperatorType type = typeMap.get(operator);
             if (type == OperatorType.BINARY_INFIX) {
-                TreeNode right = constructRecursive(matches);
+                TreeNode right = constructRecursive(matches,trace);
-                TreeNode left = constructRecursive(matches);
+                TreeNode left = constructRecursive(matches,trace);
                 if (left == null || right == null) return null;
-                else return new BinaryInfixNode(operator, left, right);
+                else return new BinaryInfixNode(operator, left, right,trace);
             } else {
-                TreeNode applyTo = constructRecursive(matches);
+                TreeNode applyTo = constructRecursive(matches,trace);
                 if (applyTo == null) return null;
-                else return new UnaryPrefixNode(operator, applyTo);
+                else return new UnaryPrefixNode(operator, applyTo,trace);
             }
         } else if (matchType == TokenType.NUM) {
             return new NumberNode(abacus.numberFromString(match.getContent()));
         } else if (matchType == TokenType.FUNCTION) {
             String functionName = match.getContent();
-            FunctionNode node = new FunctionNode(functionName);
+            FunctionNode node = new FunctionNode(functionName,trace);
             while (!matches.isEmpty() && matches.get(0).getType() != TokenType.INTERNAL_FUNCTION_END) {
-                TreeNode argument = constructRecursive(matches);
+                TreeNode argument = constructRecursive(matches,trace);
                 if (argument == null) return null;
                 node.prependChild(argument);
             }
@@ -151,10 +154,10 @@ public class ShuntingYardParser implements Parser<Match<TokenType>>, PluginListe
     }
 
     @Override
-    public TreeNode constructTree(List<Match<TokenType>> tokens) {
+    public TreeNode constructTree(List<Match<TokenType>> tokens,Abacus trace) {
         tokens = intoPostfix(new ArrayList<>(tokens));
         Collections.reverse(tokens);
-        return constructRecursive(tokens);
+        return constructRecursive(tokens,trace);
     }
 
     @Override

src/main/java/org/nwapw/abacus/parsing/TreeBuilder.java

@@ -1,5 +1,6 @@
 package org.nwapw.abacus.parsing;
 
+import org.nwapw.abacus.Abacus;
 import org.nwapw.abacus.tree.TreeNode;
 
 import java.util.List;
@@ -41,10 +42,10 @@ public class TreeBuilder<T> {
      * @param input the string to parse into a tree.
      * @return the resulting tree.
      */
-    public TreeNode fromString(String input) {
+    public TreeNode fromString(String input,Abacus trace) {
         List<T> tokens = tokenizer.tokenizeString(input);
         if (tokens == null) return null;
-        return parser.constructTree(tokens);
+        return parser.constructTree(tokens,trace);
     }
 
 }

src/main/java/org/nwapw/abacus/plugin/StandardPlugin.java

@@ -8,8 +8,6 @@ import org.nwapw.abacus.number.NaiveNumber;
 import org.nwapw.abacus.number.NumberInterface;
 import org.nwapw.abacus.number.PreciseNumber;
 
-import java.util.ArrayList;
-import java.util.HashMap;
 import java.util.function.BiFunction;
 
 /**
@@ -18,8 +16,6 @@ import java.util.function.BiFunction;
  */
 public class StandardPlugin extends Plugin {
 
-    private static HashMap<Class<? extends NumberInterface>, ArrayList<NumberInterface>> factorialLists = new HashMap<Class<? extends NumberInterface>, ArrayList<NumberInterface>>();
-
     /**
      * The addition operator, +
      */
@@ -156,40 +152,17 @@ public class StandardPlugin extends Plugin {
 
         @Override
         protected NumberInterface applyInternal(NumberInterface[] params) {
-            NumberInterface maxError = getMaxError(params[0]);
+            boolean takeReciprocal = params[0].signum() == -1;
-            int n = 0;
+            params[0] = FUNCTION_ABS.apply(params[0]);
-            if(params[0].signum() <= 0){
+            NumberInterface sum = sumSeries(params[0], StandardPlugin::getExpSeriesTerm, getNTermsExp(getMaxError(params[0]), params[0]));
-                NumberInterface currentTerm = NaiveNumber.ONE.promoteTo(params[0].getClass()), sum = currentTerm;
+            if (takeReciprocal) {
-                while(FUNCTION_ABS.apply(currentTerm).compareTo(maxError) > 0){
+                sum = NaiveNumber.ONE.promoteTo(sum.getClass()).divide(sum);
-                    n++;
-                    currentTerm = currentTerm.multiply(params[0]).divide((new NaiveNumber(n)).promoteTo(params[0].getClass()));
-                    sum = sum.add(currentTerm);
             }
             return sum;
         }
-            else{
-                //We need n such that x^(n+1) * 3^ceil(x) <= maxError * (n+1)!.
-                //right and left refer to lhs and rhs in the above inequality.
-                NumberInterface sum = NaiveNumber.ONE.promoteTo(params[0].getClass());
-                NumberInterface nextNumerator = params[0];
-                NumberInterface left = params[0].multiply((new NaiveNumber(3)).promoteTo(params[0].getClass()).intPow(params[0].ceiling())), right = maxError;
-                do{
-                    sum = sum.add(nextNumerator.divide(factorial(params[0].getClass(), n+1)));
-                    n++;
-                    nextNumerator = nextNumerator.multiply(params[0]);
-                    left = left.multiply(params[0]);
-                    NumberInterface nextN = (new NaiveNumber(n+1)).promoteTo(params[0].getClass());
-                    right = right.multiply(nextN);
-                    //System.out.println(left + ", " + right);
-                }
-                while(left.compareTo(right) > 0);
-                //System.out.println(n+1);
-                return sum;
-            }
-        }
     };
     /**
-     * The natural log function.
+     * The natural log function, ln(exp(1)) = 1
      */
     public static final Function FUNCTION_LN = new Function() {
         @Override
@@ -266,7 +239,7 @@ public class StandardPlugin extends Plugin {
         }
     };
     /**
-     * The square root function.
+     * The square root function, sqrt(4) = 2
      */
     public static final Function FUNCTION_SQRT = new Function() {
         @Override
@@ -284,6 +257,39 @@ public class StandardPlugin extends Plugin {
         super(manager);
     }
 
+    /**
+     * Returns the nth term of the Taylor series (centered at 0) of e^x
+     *
+     * @param n the term required (n >= 0).
+     * @param x the real number at which the series is evaluated.
+     * @return the nth term of the series.
+     */
+    private static NumberInterface getExpSeriesTerm(int n, NumberInterface x) {
+        return x.intPow(n).divide(OP_FACTORIAL.getFunction().apply((new NaiveNumber(n)).promoteTo(x.getClass())));
+    }
+
+    /**
+     * Returns the number of terms needed to evaluate the exponential function (at x)
+     * such that the error is at most maxError.
+     *
+     * @param maxError Maximum error permissible (This should probably be positive.)
+     * @param x        where the function is evaluated.
+     * @return the number of terms needed to evaluate the exponential function.
+     */
+    private static int getNTermsExp(NumberInterface maxError, NumberInterface x) {
+        //We need n such that |x^(n+1)| <= (n+1)! * maxError
+        //The variables LHS and RHS refer to the above inequality.
+        int n = 0;
+        x = FUNCTION_ABS.apply(x);
+        NumberInterface LHS = x, RHS = maxError;
+        while (LHS.compareTo(RHS) > 0) {
+            n++;
+            LHS = LHS.multiply(x);
+            RHS = RHS.multiply(new NaiveNumber(n + 1).promoteTo(RHS.getClass()));
+        }
+        return n;
+    }
+
     /**
      * Returns a partial sum of a series whose terms are given by the nthTermFunction, evaluated at x.
      *
@@ -333,19 +339,4 @@ public class StandardPlugin extends Plugin {
 
     }
 
-    public static NumberInterface factorial(Class<? extends NumberInterface> numberClass, int n){
-        if(!factorialLists.containsKey(numberClass)){
-            factorialLists.put(numberClass, new ArrayList<NumberInterface>());
-            factorialLists.get(numberClass).add(NaiveNumber.ONE.promoteTo(numberClass));
-            factorialLists.get(numberClass).add(NaiveNumber.ONE.promoteTo(numberClass));
-        }
-        ArrayList<NumberInterface> list = factorialLists.get(numberClass);
-        if(n >= list.size()){
-            while(list.size() < n + 16){
-                list.add(list.get(list.size()-1).multiply(new NaiveNumber(list.size()).promoteTo(numberClass)));
-            }
-        }
-        return list.get(n);
-    }
-
 }

src/main/java/org/nwapw/abacus/tree/BinaryInfixNode.java

@@ -1,5 +1,7 @@
 package org.nwapw.abacus.tree;
 
+import org.nwapw.abacus.Abacus;
+
 /**
  * A tree node that represents an operation being applied to two operands.
  */
@@ -17,6 +19,7 @@ public class BinaryInfixNode extends TreeNode {
      * The right node of the operation.
      */
     private TreeNode right;
+    private Abacus trace;
 
     private BinaryInfixNode() {
     }
@@ -27,8 +30,8 @@ public class BinaryInfixNode extends TreeNode {
      *
      * @param operation the operation.
      */
-    public BinaryInfixNode(String operation) {
+    public BinaryInfixNode(String operation,Abacus trace) {
-        this(operation, null, null);
+        this(operation, null, null,trace);
     }
 
     /**
@@ -39,10 +42,11 @@ public class BinaryInfixNode extends TreeNode {
      * @param left      the left node of the expression.
      * @param right     the right node of the expression.
      */
-    public BinaryInfixNode(String operation, TreeNode left, TreeNode right) {
+    public BinaryInfixNode(String operation, TreeNode left, TreeNode right,Abacus trace) {
         this.operation = operation;
         this.left = left;
         this.right = right;
+        this.trace = trace;
     }
 
     /**
@@ -92,11 +96,16 @@ public class BinaryInfixNode extends TreeNode {
 
     @Override
     public <T> T reduce(Reducer<T> reducer) {
+        if(!trace.getStop()) {
             T leftReduce = left.reduce(reducer);
+
             T rightReduce = right.reduce(reducer);
             if (leftReduce == null || rightReduce == null) return null;
             return reducer.reduceNode(this, leftReduce, rightReduce);
         }
+        return null;
+
+    }
 
     @Override
     public String toString() {

src/main/java/org/nwapw/abacus/tree/FunctionNode.java

@@ -1,5 +1,7 @@
 package org.nwapw.abacus.tree;
 
+import org.nwapw.abacus.Abacus;
+
 import java.util.ArrayList;
 import java.util.List;
 
@@ -16,6 +18,7 @@ public class FunctionNode extends TreeNode {
      * The list of arguments to the function.
      */
     private List<TreeNode> children;
+    private Abacus trace;
 
     /**
      * Creates a function node with no function.
@@ -28,9 +31,10 @@ public class FunctionNode extends TreeNode {
      *
      * @param function the function name.
      */
-    public FunctionNode(String function) {
+    public FunctionNode(String function,Abacus trace) {
         this.function = function;
         children = new ArrayList<>();
+        this.trace = trace;
     }
 
     /**

src/main/java/org/nwapw/abacus/tree/UnaryPrefixNode.java

@@ -1,5 +1,7 @@
 package org.nwapw.abacus.tree;
 
+import org.nwapw.abacus.Abacus;
+
 public class UnaryPrefixNode extends TreeNode {
 
     /**
@@ -10,14 +12,15 @@ public class UnaryPrefixNode extends TreeNode {
      * The tree node to apply the operation to.
      */
     private TreeNode applyTo;
+    private Abacus trace;
 
     /**
      * Creates a new node with the given operation and no child.
      *
      * @param operation the operation for this node.
      */
-    public UnaryPrefixNode(String operation) {
+    public UnaryPrefixNode(String operation,Abacus trace) {
-        this(operation, null);
+        this(operation, null,trace);
     }
 
     /**
@@ -26,17 +29,21 @@ public class UnaryPrefixNode extends TreeNode {
      * @param operation the operation for this node.
      * @param applyTo   the node to apply the function to.
      */
-    public UnaryPrefixNode(String operation, TreeNode applyTo) {
+    public UnaryPrefixNode(String operation, TreeNode applyTo,Abacus trace) {
         this.operation = operation;
         this.applyTo = applyTo;
+        this.trace = trace;
     }
 
     @Override
     public <T> T reduce(Reducer<T> reducer) {
+        if(!trace.getStop()) {
             Object reducedChild = applyTo.reduce(reducer);
             if (reducedChild == null) return null;
             return reducer.reduceNode(this, reducedChild);
         }
+        return null;
+    }
 
     /**
      * Gets the operation of this node.

src/main/java/org/nwapw/abacus/window/Window.java

@@ -16,12 +16,13 @@ import java.awt.event.MouseEvent;
  */
 public class Window extends JFrame {
     
+
     private static final String CALC_STRING = "Calculate";
     private static final String SYNTAX_ERR_STRING = "Syntax Error";
     private static final String EVAL_ERR_STRING = "Evaluation Error";
     private static final String NUMBER_SYSTEM_LABEL = "Number Type:";
     private static final String FUNCTION_LABEL = "Functions:";
-
+    private static final String STOP_STRING = "Stop";
     /**
      * Array of Strings to which the "calculate" button's text
      * changes. For instance, in the graph tab, the name will
@@ -90,7 +91,10 @@ public class Window extends JFrame {
      * The "submit" button.
      */
     private JButton inputEnterButton;
-
+    /**
+     * The stop calculations button.
+     */
+    private JButton inputStopButton;
     /**
      * The side panel for separate configuration.
      */
@@ -113,26 +117,80 @@ public class Window extends JFrame {
      * The list of functions available to the user.
      */
     private JComboBox<String> functionList;
+    /**
+     * Thread used for calculations
+     */
+    private Thread calculateThread;
+    /**
+     * Check if currently calculating.
+     */
+    private boolean calculating;
+    /**
+     * Checks if thread should stop calculating.
+     */
+    private boolean stopCalculating;
+    /**
+     * Test variable to check number of threads running in the calculator.
+     */
+    private int count;
+    /**
+     * ActionListener that stops calculations.
+     */
+    private ActionListener stopListener = (event) -> {
+        //System.out.println(count++);  //Shows about how many calculation threads are running with the calculating=false command
+        //calculating = false;          //Ignores result of calculation and allows for the start of a new calculation
+        stopCalculating = true;         //Stops calculation at the next node check
+        //calculateThread.stop();         //Stops thread no matter what, Unsafe
+    };
 
     /**
-     * Action listener that causes the input to be evaluated.
+     * Node check to get whether nodes should continue calculating.
+     * @return boolean stop calculations if true.
+     */
+    public boolean getStop(){
+        return stopCalculating;
+    }
+
+    /**
+     * ActionListener that runs all calculations.
      */
     private ActionListener evaluateListener = (event) -> {
-        TreeNode parsedExpression = abacus.parseString(inputField.getText());
+        Runnable calculate = new Runnable() {
+            public void run() {
+                boolean skip = false;
+                calculating = true;
+                TreeNode parsedExpression = null;
+                parsedExpression = abacus.parseString(inputField.getText());
                 if (parsedExpression == null) {
                     lastOutputArea.setText(SYNTAX_ERR_STRING);
-            return;
+                    skip = true;
                 }
+                if(!skip){
                     NumberInterface numberInterface = abacus.evaluateTree(parsedExpression);
                     if (numberInterface == null) {
                         lastOutputArea.setText(EVAL_ERR_STRING);
+                        calculating = false;
+                        stopCalculating = false;
+
                         return;
                     }
+                    if(calculateThread.equals(Thread.currentThread())) {
                         lastOutput = numberInterface.toString();
                         historyModel.addEntry(new HistoryTableModel.HistoryEntry(inputField.getText(), parsedExpression, lastOutput));
                         historyTable.invalidate();
                         lastOutputArea.setText(lastOutput);
                         inputField.setText("");
+                        calculating = false;
+                        stopCalculating = false;
+                    }
+                }
+            }
+        };
+        if(!calculating) {
+            calculateThread = new Thread(calculate);
+            calculateThread.setName("a-"+System.currentTimeMillis());
+            calculateThread.start();
+        }
     };
 
     /**
@@ -143,6 +201,14 @@ public class Window extends JFrame {
             evaluateListener,
             null
     };
+    /**
+     * Array of listeners that tell the stop button how to behave
+     * at a given input tab.
+     */
+    private ActionListener[] stopListeners = {
+            stopListener,
+            null
+    };
 
     /**
      * Creates a new window with the given manager.
@@ -152,6 +218,7 @@ public class Window extends JFrame {
     public Window(Abacus abacus) {
         this();
         this.abacus = abacus;
+        abacus.setWindow(this);
     }
 
     /**
@@ -160,25 +227,36 @@ public class Window extends JFrame {
     private Window() {
         super();
 
+        //variables related to when calculations occur
+        stopCalculating = false;
+        calculating = true;
+
         lastOutput = "";
 
+        //default window properties
         setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
         setSize(320, 480);
 
+        //initiates input objects
         inputField = new JTextField();
         inputEnterButton = new JButton(CALC_STRING);
+        inputStopButton = new JButton(STOP_STRING);
 
+        //adds input objects into Panel
         inputPanel = new JPanel();
         inputPanel.setLayout(new BorderLayout());
-        inputPanel.add(inputField, BorderLayout.CENTER);
+        inputPanel.add(inputStopButton, BorderLayout.SOUTH);
-        inputPanel.add(inputEnterButton, BorderLayout.SOUTH);
+        inputPanel.add(inputField, BorderLayout.NORTH);
+        inputPanel.add(inputEnterButton, BorderLayout.CENTER);
 
+        //initiates output objects in calculator tab
         historyModel = new HistoryTableModel();
         historyTable = new JTable(historyModel);
         historyScroll = new JScrollPane(historyTable);
         lastOutputArea = new JTextArea(lastOutput);
         lastOutputArea.setEditable(false);
 
+        //adds output objects into Panel
         calculationPanel = new JPanel();
         calculationPanel.setLayout(new BorderLayout());
         calculationPanel.add(historyScroll, BorderLayout.CENTER);
@@ -208,6 +286,8 @@ public class Window extends JFrame {
         settingsPanel.add(numberSystemPanel);
         settingsPanel.add(functionSelectPanel);
 
+        calculating = false;
+
         pane = new JTabbedPane();
         pane.add("Calculator", calculationPanel);
         pane.add("Settings", settingsPanel);
@@ -215,17 +295,23 @@ public class Window extends JFrame {
             int selectionIndex = pane.getSelectedIndex();
             boolean enabled = INPUT_ENABLED[selectionIndex];
             ActionListener listener = listeners[selectionIndex];
+            ActionListener stopUsed = stopListeners[selectionIndex];
             inputEnterButton.setText(BUTTON_NAMES[selectionIndex]);
             inputField.setEnabled(enabled);
             inputEnterButton.setEnabled(enabled);
+            inputStopButton.setEnabled(enabled);
 
             for (ActionListener removingListener : inputEnterButton.getActionListeners()) {
                 inputEnterButton.removeActionListener(removingListener);
                 inputField.removeActionListener(removingListener);
             }
+            for(ActionListener removingListener : inputStopButton.getActionListeners()){
+                inputStopButton.removeActionListener(removingListener);
+            }
             if (listener != null) {
                 inputEnterButton.addActionListener(listener);
                 inputField.addActionListener(listener);
+                inputStopButton.addActionListener(stopUsed);
             }
         });
         add(pane, BorderLayout.CENTER);
@@ -233,6 +319,7 @@ public class Window extends JFrame {
 
         inputEnterButton.addActionListener(evaluateListener);
         inputField.addActionListener(evaluateListener);
+        inputStopButton.addActionListener(stopListener);
         historyTable.addMouseListener(new MouseAdapter() {
             @Override
             public void mouseClicked(MouseEvent e) {

src/main/resources/abacus.fxml

@@ -1,46 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-
-<?import javafx.geometry.Insets?>
-<?import javafx.scene.control.*?>
-<?import javafx.scene.layout.BorderPane?>
-<?import javafx.scene.layout.VBox?>
-<?import javafx.scene.text.Text?>
-<BorderPane xmlns="http://javafx.com/javafx"
-            xmlns:fx="http://javafx.com/fxml"
-            fx:controller="org.nwapw.abacus.fx.AbacusController">
-    <center>
-        <TabPane>
-            <Tab text="Calculator" closable="false">
-                <BorderPane>
-                    <center>
-                        <TableView fx:id="historyTable">
-                            <columnResizePolicy>
-                                <TableView fx:constant="CONSTRAINED_RESIZE_POLICY"/>
-                            </columnResizePolicy>
-                            <columns>
-                                <TableColumn fx:id="inputColumn" text="Input" sortable="false"/>
-                                <TableColumn fx:id="parsedColumn" text="Parsed" sortable="false"/>
-                                <TableColumn fx:id="outputColumn" text="Output" sortable="false"/>
-                            </columns>
-                        </TableView>
-                    </center>
-                    <bottom>
-                        <VBox>
-                            <ScrollPane prefHeight="50" vbarPolicy="NEVER">
-                                <padding>
-                                    <Insets top="10" bottom="10" left="10" right="10"/>
-                                </padding>
-                                <Text fx:id="outputText"/>
-                            </ScrollPane>
-                            <TextField fx:id="inputField" onAction="#performCalculation"/>
-                            <Button fx:id="inputButton" text="Calculate" maxWidth="Infinity"
-                                    onAction="#performCalculation"/>
-                        </VBox>
-                    </bottom>
-                </BorderPane>
-            </Tab>
-            <Tab text="Settings" closable="false"/>
-        </TabPane>
-    </center>
-
-</BorderPane>