Add some tests to pow.

build.gradle

@@ -1,8 +1,3 @@
-plugins {
-    id 'java'
-    id 'application'
-    id 'org.jetbrains.kotlin.jvm' version '1.1.3'
-}
 apply plugin: 'java'
 apply plugin: 'application'
 
@@ -12,7 +7,6 @@ repositories {
 
 dependencies {
     compile 'com.moandjiezana.toml:toml4j:0.7.1'
-    compile "org.jetbrains.kotlin:kotlin-stdlib-jre8"
     testCompile 'junit:junit:4.12'
 }
 

src/main/java/org/nwapw/abacus/function/DocumentationType.java

@@ -1,7 +0,0 @@
-package org.nwapw.abacus.function;
-
-public enum DocumentationType {
-
-    FUNCTION
-
-}

src/main/java/org/nwapw/abacus/function/Operator.java

@@ -0,0 +1,76 @@
+package org.nwapw.abacus.function;
+
+/**
+ * A class that represents a single infix operator.
+ */
+public class Operator {
+
+    /**
+     * The associativity of the operator.
+     */
+    private OperatorAssociativity associativity;
+    /**
+     * The type of this operator.
+     */
+    private OperatorType type;
+    /**
+     * The precedence of the operator.
+     */
+    private int precedence;
+    /**
+     * The function that is called by this operator.
+     */
+    private Function function;
+
+    /**
+     * Creates a new operator with the given parameters.
+     *
+     * @param associativity the associativity of the operator.
+     * @param operatorType  the type of this operator, like binary infix or unary postfix.
+     * @param precedence    the precedence of the operator.
+     * @param function      the function that the operator calls.
+     */
+    public Operator(OperatorAssociativity associativity, OperatorType operatorType, int precedence, Function function) {
+        this.associativity = associativity;
+        this.type = operatorType;
+        this.precedence = precedence;
+        this.function = function;
+    }
+
+    /**
+     * Gets the operator's associativity.
+     *
+     * @return the associativity.
+     */
+    public OperatorAssociativity getAssociativity() {
+        return associativity;
+    }
+
+    /**
+     * Gets the operator's type.
+     *
+     * @return the type.
+     */
+    public OperatorType getType() {
+        return type;
+    }
+
+    /**
+     * Gets the operator's precedence.
+     *
+     * @return the precedence.
+     */
+    public int getPrecedence() {
+        return precedence;
+    }
+
+    /**
+     * Gets the operator's function.
+     *
+     * @return the function.
+     */
+    public Function getFunction() {
+        return function;
+    }
+
+}

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

@@ -5,9 +5,7 @@ import javafx.beans.value.ChangeListener;
 import javafx.beans.value.ObservableValue;
 import javafx.collections.FXCollections;
 import javafx.collections.ObservableList;
-import javafx.collections.transformation.FilteredList;
 import javafx.fxml.FXML;
-import javafx.scene.Node;
 import javafx.scene.control.*;
 import javafx.scene.control.cell.CheckBoxListCell;
 import javafx.scene.text.Text;
@@ -15,8 +13,6 @@ import javafx.util.Callback;
 import javafx.util.StringConverter;
 import org.nwapw.abacus.Abacus;
 import org.nwapw.abacus.config.Configuration;
-import org.nwapw.abacus.function.Documentation;
-import org.nwapw.abacus.function.DocumentationType;
 import org.nwapw.abacus.number.ComputationInterruptedException;
 import org.nwapw.abacus.number.NumberInterface;
 import org.nwapw.abacus.plugin.ClassFinder;
@@ -27,10 +23,7 @@ import org.nwapw.abacus.tree.TreeNode;
 
 import java.io.File;
 import java.io.IOException;
-import java.util.ArrayList;
-import java.util.Comparator;
 import java.util.Set;
-import java.util.stream.Collectors;
 
 
 /**
@@ -79,8 +72,6 @@ public class AbacusController implements PluginListener {
     @FXML
     private Tab settingsTab;
     @FXML
-    private Tab functionListTab;
-    @FXML
     private TableView<HistoryModel> historyTable;
     @FXML
     private TableColumn<HistoryModel, String> inputColumn;
@@ -102,10 +93,6 @@ public class AbacusController implements PluginListener {
     private ListView<ToggleablePlugin> enabledPluginView;
     @FXML
     private TextField computationLimitField;
-    @FXML
-    private ListView<Documentation> functionListView;
-    @FXML
-    private TextField functionListSearchField;
 
     /**
      * The list of history entries, created by the users.
@@ -123,14 +110,6 @@ public class AbacusController implements PluginListener {
      * and, when reloaded, get added to the plugin manager's black list.
      */
     private ObservableList<ToggleablePlugin> enabledPlugins;
-    /**
-     * The list of functions that are registered in the calculator.
-     */
-    private ObservableList<Documentation> functionList;
-    /**
-     * The filtered list displayed to the user.
-     */
-    private FilteredList<Documentation> functionFilter;
 
     /**
      * The abacus instance used for changing the plugin configuration.
@@ -233,12 +212,7 @@ public class AbacusController implements PluginListener {
                         return new ToggleablePlugin(true, string);
                     }
                 });
-        functionList = FXCollections.observableArrayList();
+
-        functionFilter = new FilteredList<>(functionList, (s) -> true);
-        functionListView.setItems(functionFilter);
-        functionListSearchField.textProperty().addListener((observable, oldValue, newValue) ->
-                functionFilter.setPredicate((newValue.length() == 0) ? ((s) -> true) : ((s) -> s.matches(newValue))));
-        functionListView.setCellFactory(param -> new DocumentationCell());
         historyData = FXCollections.observableArrayList();
         historyTable.setItems(historyData);
         numberImplementationOptions = FXCollections.observableArrayList();
@@ -353,15 +327,10 @@ public class AbacusController implements PluginListener {
             plugin.enabledProperty().addListener(e -> changesMade = true);
             enabledPlugins.add(plugin);
         }
-        PluginManager pluginManager = abacus.getPluginManager();
-        functionList.addAll(manager.getAllFunctions().stream().map(name -> pluginManager.documentationFor(name, DocumentationType.FUNCTION))
-                .collect(Collectors.toCollection(ArrayList::new)));
-        functionList.sort(Comparator.comparing(Documentation::getCodeName));
     }
 
     @Override
     public void onUnload(PluginManager manager) {
-        functionList.clear();
         enabledPlugins.clear();
         numberImplementationOptions.clear();
     }

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

@@ -1,58 +0,0 @@
-package org.nwapw.abacus.fx;
-
-import javafx.scene.control.Label;
-import javafx.scene.control.ListCell;
-import javafx.scene.control.TitledPane;
-import javafx.scene.layout.VBox;
-import org.nwapw.abacus.function.Documentation;
-
-public class DocumentationCell extends ListCell<Documentation> {
-
-    private Label codeNameLabel;
-    private Label nameLabel;
-    private Label description;
-    private Label longDescription;
-    private TitledPane titledPane;
-
-    public DocumentationCell(){
-        VBox vbox = new VBox();
-        vbox.setSpacing(10);
-        titledPane = new TitledPane();
-        codeNameLabel = new Label();
-        nameLabel = new Label();
-        description = new Label();
-        longDescription = new Label();
-        codeNameLabel.setWrapText(true);
-        nameLabel.setWrapText(true);
-        description.setWrapText(true);
-        longDescription.setWrapText(true);
-        vbox.getChildren().add(codeNameLabel);
-        vbox.getChildren().add(nameLabel);
-        vbox.getChildren().add(description);
-        vbox.getChildren().add(longDescription);
-        titledPane.textProperty().bindBidirectional(codeNameLabel.textProperty());
-        titledPane.setContent(vbox);
-        titledPane.setExpanded(false);
-        titledPane.prefWidthProperty().bind(widthProperty());
-
-        visibleProperty().addListener((a, b, c) -> titledPane.setExpanded(false));
-    }
-
-    @Override
-    protected void updateItem(Documentation item, boolean empty) {
-        super.updateItem(item, empty);
-        if(empty){
-            codeNameLabel.setText("");
-            nameLabel.setText("");
-            description.setText("");
-            longDescription.setText("");
-            setGraphic(null);
-        } else {
-            codeNameLabel.setText(item.getCodeName());
-            nameLabel.setText(item.getName());
-            description.setText(item.getDescription());
-            longDescription.setText(item.getLongDescription());
-            setGraphic(titledPane);
-        }
-    }
-}

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

@@ -128,5 +128,9 @@ public class NaiveNumber extends NumberInterface {
         return Double.toString(Math.round(value * shiftBy) / shiftBy);
     }
 
+    @Override
+    public NumberInterface getMaxError(){
+        return new NaiveNumber(Math.pow(10, -18));
+    }
 }
 

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

@@ -255,4 +255,11 @@ public abstract class NumberInterface {
         return promoteToInternal(toClass);
     }
 
+    /**
+     * Returns the smallest error this instance can tolerate depending
+     * on its precision and value.
+     * @return the smallest error that should be permitted in calculations.
+     */
+    public abstract NumberInterface getMaxError();
+
 }

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

@@ -1,7 +1,7 @@
 package org.nwapw.abacus.number;
 
 import java.math.BigDecimal;
-import java.math.RoundingMode;
+import java.math.MathContext;
 
 /**
  * A number that uses a BigDecimal to store its value,
@@ -22,6 +22,21 @@ public class PreciseNumber extends NumberInterface {
      */
     public static final PreciseNumber TEN = new PreciseNumber(BigDecimal.TEN);
 
+    /**
+     * The number of extra significant figures kept in calculations before rounding for output.
+     */
+    private static int numExtraInternalSigFigs = 15;
+
+    /**
+     * MathContext that is used when rounding a number prior to output.
+     */
+    private static MathContext outputContext = new MathContext(50);
+
+    /**
+     * MathContext that is actually used in calculations.
+     */
+    private static MathContext internalContext = new MathContext(outputContext.getPrecision()+numExtraInternalSigFigs);
+
     /**
      * The value of the PreciseNumber.
      */
@@ -48,7 +63,7 @@ public class PreciseNumber extends NumberInterface {
 
     @Override
     public int getMaxPrecision() {
-        return 65;
+        return internalContext.getPrecision();
     }
 
     @Override
@@ -58,7 +73,7 @@ public class PreciseNumber extends NumberInterface {
 
     @Override
     public NumberInterface divideInternal(NumberInterface divisor) {
-        return new PreciseNumber(value.divide(((PreciseNumber) divisor).value, this.getMaxPrecision(), RoundingMode.HALF_UP));
+        return new PreciseNumber(value.divide(((PreciseNumber) divisor).value, internalContext));
     }
 
     @Override
@@ -147,7 +162,11 @@ public class PreciseNumber extends NumberInterface {
 
     @Override
     public String toString() {
-        BigDecimal rounded = value.setScale(getMaxPrecision() - 15, RoundingMode.HALF_UP);
+        return value.round(outputContext).toString();
-        return rounded.stripTrailingZeros().toPlainString();
+    }
+
+    @Override
+    public NumberInterface getMaxError(){
+        return new PreciseNumber(value.ulp()).multiplyInternal(TEN.intPowInternal(value.precision()-internalContext.getPrecision()));
     }
 }

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

@@ -1,7 +1,5 @@
 package org.nwapw.abacus.plugin;
 
-import org.nwapw.abacus.function.Documentation;
-import org.nwapw.abacus.function.DocumentationType;
 import org.nwapw.abacus.function.Function;
 import org.nwapw.abacus.function.Operator;
 import org.nwapw.abacus.number.NumberInterface;
@@ -96,15 +94,6 @@ public abstract class Plugin {
         manager.registerNumberImplementation(name, implementation);
     }
 
-    /**
-     * To be used in load(). Registers a documentation instance
-     * used to explain some element of the plugin to the user.
-     * @param documentation the documentation instance.
-     */
-    protected final void registerDocumentation(Documentation documentation){
-        manager.registerDocumentation(documentation);
-    }
-
     /**
      * Searches the PluginManager for the given function name.
      * This can be used by the plugins internally in order to call functions
@@ -141,17 +130,6 @@ public abstract class Plugin {
         return manager.numberImplementationFor(name);
     }
 
-    /**
-     * Searches the PluginManager for the given documentation name and type.
-     *
-     * @param name the name for which to search.
-     * @param type the type of documentation to search for.
-     * @return the found documentation, or null if none was found.
-     */
-    protected final Documentation documentationFor(String name, DocumentationType type){
-        return manager.documentationFor(name, type);
-    }
-
     /**
      * Searches the plugin manager for a Pi value for the given number implementation.
      * This is done so that number implementations with various degrees of precision

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

@@ -1,8 +1,6 @@
 package org.nwapw.abacus.plugin;
 
 import org.nwapw.abacus.Abacus;
-import org.nwapw.abacus.function.Documentation;
-import org.nwapw.abacus.function.DocumentationType;
 import org.nwapw.abacus.function.Function;
 import org.nwapw.abacus.function.Operator;
 import org.nwapw.abacus.number.NumberInterface;
@@ -36,10 +34,6 @@ public class PluginManager {
      * The map of number implementations registered by the plugins.
      */
     private Map<String, NumberImplementation> registeredNumberImplementations;
-    /**
-     * The map of documentation for functions registered by the plugins.
-     */
-    private Set<Documentation> registeredDocumentation;
     /**
      * The list of number implementations that have been
      * found by their implementation class.
@@ -71,7 +65,6 @@ public class PluginManager {
         registeredFunctions = new HashMap<>();
         registeredOperators = new HashMap<>();
         registeredNumberImplementations = new HashMap<>();
-        registeredDocumentation = new HashSet<>();
         cachedInterfaceImplementations = new HashMap<>();
         cachedPi = new HashMap<>();
         listeners = new HashSet<>();
@@ -104,15 +97,6 @@ public class PluginManager {
         registeredNumberImplementations.put(name, implementation);
     }
 
-    /**
-     * Registers the given documentation with the plugin manager,
-     * making it accessible to the plugin manager etc.
-     * @param documentation the documentation to register.
-     */
-    public void registerDocumentation(Documentation documentation){
-        registeredDocumentation.add(documentation);
-    }
-
     /**
      * Gets the function registered under the given name.
      * @param name the name of the function.
@@ -140,27 +124,6 @@ public class PluginManager {
         return registeredNumberImplementations.get(name);
     }
 
-    /**
-     * Gets the documentation for the given entity of the given type.
-     * @param name the name of the entity to search for.
-     * @param type the type that this entity is, to filter out similarly named documentation.
-     * @return the documentation object.
-     */
-    public Documentation documentationFor(String name, DocumentationType type){
-        Documentation toReturn = null;
-        for(Documentation entry : registeredDocumentation){
-            if(entry.getCodeName().equals(name) && entry.getType() == type) {
-                toReturn = entry;
-                break;
-            }
-        }
-        if(toReturn == null){
-            toReturn = new Documentation(name, "", "", "", type);
-            registerDocumentation(toReturn);
-        }
-        return toReturn;
-    }
-
     /**
      * Gets the number implementation for the given implementation class.
      *
@@ -246,10 +209,6 @@ public class PluginManager {
             if (disabledPlugins.contains(plugin.getClass().getName())) continue;
             plugin.disable();
         }
-        registeredFunctions.clear();
-        registeredOperators.clear();
-        registeredNumberImplementations.clear();
-        registeredDocumentation.clear();
         cachedInterfaceImplementations.clear();
         cachedPi.clear();
         listeners.forEach(e -> e.onUnload(this));

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

@@ -1,18 +1,15 @@
 package org.nwapw.abacus.plugin;
 
-import org.nwapw.abacus.function.*;
+import org.nwapw.abacus.function.Function;
-import org.nwapw.abacus.lexing.pattern.Match;
+import org.nwapw.abacus.function.Operator;
+import org.nwapw.abacus.function.OperatorAssociativity;
+import org.nwapw.abacus.function.OperatorType;
 import org.nwapw.abacus.number.NaiveNumber;
 import org.nwapw.abacus.number.NumberInterface;
 import org.nwapw.abacus.number.PreciseNumber;
-import org.nwapw.abacus.parsing.Parser;
-import org.nwapw.abacus.parsing.ShuntingYardParser;
-import org.nwapw.abacus.tree.TokenType;
-import org.nwapw.abacus.tree.TreeNode;
 
 import java.util.ArrayList;
 import java.util.HashMap;
-import java.util.List;
 import java.util.function.BiFunction;
 
 /**
@@ -191,7 +188,7 @@ public class StandardPlugin extends Plugin {
          */
         private NumberInterface getLogPartialSum(NumberInterface x) {
 
-            NumberInterface maxError = getMaxError(x);
+            NumberInterface maxError = x.getMaxError();
             x = x.subtract(NaiveNumber.ONE.promoteTo(x.getClass())); //Terms used are for log(x+1).
             NumberInterface currentNumerator = x, currentTerm = x, sum = x;
             int n = 1;
@@ -210,7 +207,7 @@ public class StandardPlugin extends Plugin {
          * @return the value of log(2) with the appropriate precision.
          */
         private NumberInterface getLog2(NumberInterface number) {
-            NumberInterface maxError = getMaxError(number);
+            NumberInterface maxError = number.getMaxError();
             //NumberInterface errorBound = fromInt(number.getClass(), 1);
             //We'll use the series \sigma_{n >= 1) ((1/3^n + 1/4^n) * 1/n)
             //In the following, a=1/3^n, b=1/4^n, c = 1/n.
@@ -304,16 +301,11 @@ public class StandardPlugin extends Plugin {
 
         @Override
         protected NumberInterface applyInternal(NumberInterface[] params) {
-            NumberInterface maxError = getMaxError(params[0]);
+            NumberInterface maxError = params[0].getMaxError();
             int n = 0;
-            if (params[0].signum() <= 0) {
+            if (params[0].signum() < 0) {
-                NumberInterface currentTerm = NaiveNumber.ONE.promoteTo(params[0].getClass()), sum = currentTerm;
+                NumberInterface[] negatedParams = {params[0].negate()};
-                while (FUNCTION_ABS.apply(currentTerm).compareTo(maxError) > 0) {
+               return fromInt(params[0].getClass(), 1).divide(applyInternal(negatedParams));
-                    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.
@@ -355,7 +347,7 @@ public class StandardPlugin extends Plugin {
                 return NaiveNumber.ONE.promoteTo(params[1].getClass());
             //Detect integer bases:
             if(params[0].fractionalPart().compareTo(fromInt(params[0].getClass(), 0)) == 0
-                    && FUNCTION_ABS.apply(params[0]).compareTo(fromInt(params[0].getClass(), Integer.MAX_VALUE)) < 0
+                    && FUNCTION_ABS.apply(params[1]).compareTo(fromInt(params[0].getClass(), Integer.MAX_VALUE)) < 0
                     && FUNCTION_ABS.apply(params[1]).compareTo(fromInt(params[1].getClass(), 1)) >= 0){
                 NumberInterface[] newParams = {params[0], params[1].fractionalPart()};
                 return params[0].intPow(params[1].floor().intValue()).multiply(applyInternal(newParams));
@@ -479,16 +471,6 @@ public class StandardPlugin extends Plugin {
         return sum;
     }
 
-    /**
-     * Returns the maximum error based on the precision of the class of number.
-     *
-     * @param number Any instance of the NumberInterface in question (should return an appropriate precision).
-     * @return the maximum error.
-     */
-    private static NumberInterface getMaxError(NumberInterface number) {
-        return fromInt(number.getClass(), 10).intPow(-number.getMaxPrecision());
-    }
-
     /**
      * A factorial function that uses memoization for each number class; it efficiently
      * computes factorials of non-negative integers.
@@ -520,7 +502,7 @@ public class StandardPlugin extends Plugin {
      */
     private static NumberInterface sinTaylor(NumberInterface x) {
         NumberInterface power = x, multiplier = x.multiply(x).negate(), currentTerm = x, sum = x;
-        NumberInterface maxError = getMaxError(x);
+        NumberInterface maxError = x.getMaxError();
         int n = 1;
         do {
             n += 2;
@@ -586,35 +568,6 @@ public class StandardPlugin extends Plugin {
         registerFunction("sec", functionSec);
         registerFunction("csc", functionCsc);
         registerFunction("cot", functionCot);
-
-        registerDocumentation(new Documentation("abs", "Absolute Value", "Finds the distance " +
-                "from zero of a number.", "Given a number, this function finds the distance form " +
-                "zero of a number, effectively turning negative numbers into positive ones.\n\n" +
-                "Example: abs(-2) -> 2", DocumentationType.FUNCTION));
-        registerDocumentation(new Documentation("exp", "Exponentiate", "Brings e to the given power.",
-                "This function evaluates e to the power of the given value, and is the inverse " +
-                        "of the natural logarithm.\n\n" +
-                        "Example: exp(1) -> 2.718...", DocumentationType.FUNCTION));
-        registerDocumentation(new Documentation("ln", "Natural Logarithm", "Gets the natural " +
-                "logarithm of the given value.", "The natural logarithm of a number is " +
-                "the power that e has to be brought to to be equal to the number.\n\n" +
-                "Example: ln(2.718) -> 1", DocumentationType.FUNCTION));
-        registerDocumentation(new Documentation("sqrt", "Square Root", "Finds the square root " +
-                "of the number.", "A square root a of a number is defined such that a times a is equal " +
-                "to that number.\n\n" +
-                "Example: sqrt(4) -> 2", DocumentationType.FUNCTION));
-        registerDocumentation(new Documentation("sin", "Sine", "Computes the sine of the given angle, " +
-                "in radians.", "", DocumentationType.FUNCTION));
-        registerDocumentation(new Documentation("cos", "Cosine", "Computes the cosine of the given angle, " +
-                "in radians.", "", DocumentationType.FUNCTION));
-        registerDocumentation(new Documentation("tan", "Tangent", "Computes the tangent of the given angle, " +
-                "in radians.", "", DocumentationType.FUNCTION));
-        registerDocumentation(new Documentation("sec", "Secant", "Computes the secant of the given angle, " +
-                "in radians.", "", DocumentationType.FUNCTION));
-        registerDocumentation(new Documentation("csc", "Cosecant", "Computes the cosecant of the given angle, " +
-                "in radians.", "", DocumentationType.FUNCTION));
-        registerDocumentation(new Documentation("cot", "Cotangent", "Computes the cotangent of the given angle, " +
-                "in radians.", "", DocumentationType.FUNCTION));
     }
 
     @Override

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

@@ -0,0 +1,108 @@
+package org.nwapw.abacus.tree;
+
+/**
+ * A tree node that represents an operation being applied to two operands.
+ */
+public class BinaryNode extends TreeNode {
+
+    /**
+     * The operation being applied.
+     */
+    private String operation;
+    /**
+     * The left node of the operation.
+     */
+    private TreeNode left;
+    /**
+     * The right node of the operation.
+     */
+    private TreeNode right;
+
+    private BinaryNode() {
+    }
+
+    /**
+     * Creates a new operation node with the given operation
+     * and no child nodes.
+     *
+     * @param operation the operation.
+     */
+    public BinaryNode(String operation) {
+        this(operation, null, null);
+    }
+
+    /**
+     * Creates a new operation node with the given operation
+     * and child nodes.
+     *
+     * @param operation the operation.
+     * @param left      the left node of the expression.
+     * @param right     the right node of the expression.
+     */
+    public BinaryNode(String operation, TreeNode left, TreeNode right) {
+        this.operation = operation;
+        this.left = left;
+        this.right = right;
+    }
+
+    /**
+     * Gets the operation in this node.
+     *
+     * @return the operation in this node.
+     */
+    public String getOperation() {
+        return operation;
+    }
+
+    /**
+     * Gets the left sub-expression of this node.
+     *
+     * @return the left node.
+     */
+    public TreeNode getLeft() {
+        return left;
+    }
+
+    /**
+     * Sets the left sub-expression of this node.
+     *
+     * @param left the sub-expression to apply.
+     */
+    public void setLeft(TreeNode left) {
+        this.left = left;
+    }
+
+    /**
+     * Gets the right sub-expression of this node.
+     *
+     * @return the right node.
+     */
+    public TreeNode getRight() {
+        return right;
+    }
+
+    /**
+     * Sets the right sub-expression of this node.
+     *
+     * @param right the sub-expression to apply.
+     */
+    public void setRight(TreeNode right) {
+        this.right = right;
+    }
+
+    @Override
+    public <T> T reduce(Reducer<T> reducer) {
+        T leftReduce = left.reduce(reducer);
+        T rightReduce = right.reduce(reducer);
+        if (leftReduce == null || rightReduce == null) return null;
+        return reducer.reduceNode(this, leftReduce, rightReduce);
+    }
+
+    @Override
+    public String toString() {
+        String leftString = left != null ? left.toString() : "null";
+        String rightString = right != null ? right.toString() : "null";
+
+        return "(" + leftString + operation + rightString + ")";
+    }
+}

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

@@ -0,0 +1,85 @@
+package org.nwapw.abacus.tree;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * A node that represents a function call.
+ */
+public class FunctionNode extends TreeNode {
+
+    /**
+     * The name of the function being called
+     */
+    private String function;
+    /**
+     * The list of arguments to the function.
+     */
+    private List<TreeNode> children;
+
+    /**
+     * Creates a function node with no function.
+     */
+    private FunctionNode() {
+    }
+
+    /**
+     * Creates a new function node with the given function name.
+     *
+     * @param function the function name.
+     */
+    public FunctionNode(String function) {
+        this.function = function;
+        children = new ArrayList<>();
+    }
+
+    /**
+     * Gets the function name for this node.
+     *
+     * @return the function name.
+     */
+    public String getFunction() {
+        return function;
+    }
+
+    /**
+     * Adds a child to the end of this node's child list.
+     *
+     * @param node the child to add.
+     */
+    public void appendChild(TreeNode node) {
+        children.add(node);
+    }
+
+    /**
+     * Adds a new child to the beginning of this node's child list.
+     *
+     * @param node the node to add.
+     */
+    public void prependChild(TreeNode node) {
+        children.add(0, node);
+    }
+
+    @Override
+    public <T> T reduce(Reducer<T> reducer) {
+        Object[] reducedChildren = new Object[children.size()];
+        for (int i = 0; i < reducedChildren.length; i++) {
+            reducedChildren[i] = children.get(i).reduce(reducer);
+            if (reducedChildren[i] == null) return null;
+        }
+        return reducer.reduceNode(this, reducedChildren);
+    }
+
+    @Override
+    public String toString() {
+        StringBuilder buffer = new StringBuilder();
+        buffer.append(function);
+        buffer.append("(");
+        for (int i = 0; i < children.size(); i++) {
+            buffer.append(children.get(i));
+            buffer.append(i == children.size() - 1 ? "" : ", ");
+        }
+        buffer.append(")");
+        return buffer.toString();
+    }
+}

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

@@ -0,0 +1,49 @@
+package org.nwapw.abacus.tree;
+
+import org.nwapw.abacus.number.NumberInterface;
+
+/**
+ * A node implementation that represents a single number.
+ */
+public class NumberNode extends TreeNode {
+
+    /**
+     * The number that is represented by this number node.
+     */
+    private NumberInterface number;
+
+    /**
+     * Creates a number node with no number.
+     */
+    public NumberNode() {
+        number = null;
+    }
+
+    /**
+     * Creates a new number node with the given double value.
+     *
+     * @param newNumber the number for which to create a number node.
+     */
+    public NumberNode(NumberInterface newNumber) {
+        this.number = newNumber;
+    }
+
+    /**
+     * Gets the number value of this node.
+     *
+     * @return the number value of this node.
+     */
+    public NumberInterface getNumber() {
+        return number;
+    }
+
+    @Override
+    public <T> T reduce(Reducer<T> reducer) {
+        return reducer.reduceNode(this);
+    }
+
+    @Override
+    public String toString() {
+        return number != null ? number.toString() : "null";
+    }
+}

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

@@ -0,0 +1,17 @@
+package org.nwapw.abacus.tree;
+
+/**
+ * An abstract class that represents an expression tree node.
+ */
+public abstract class TreeNode {
+
+    /**
+     * The function that reduces a tree to a single vale.
+     *
+     * @param reducer the reducer used to reduce the tree.
+     * @param <T>     the type the reducer produces.
+     * @return the result of the reduction, or null on error.
+     */
+    public abstract <T> T reduce(Reducer<T> reducer);
+
+}

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

@@ -0,0 +1,63 @@
+package org.nwapw.abacus.tree;
+
+public class UnaryNode extends TreeNode {
+
+    /**
+     * The operation this node will apply.
+     */
+    private String operation;
+    /**
+     * The tree node to apply the operation to.
+     */
+    private TreeNode applyTo;
+
+    /**
+     * Creates a new node with the given operation and no child.
+     *
+     * @param operation the operation for this node.
+     */
+    public UnaryNode(String operation) {
+        this(operation, null);
+    }
+
+    /**
+     * Creates a new node with the given operation and child.
+     *
+     * @param operation the operation for this node.
+     * @param applyTo   the node to apply the function to.
+     */
+    public UnaryNode(String operation, TreeNode applyTo) {
+        this.operation = operation;
+        this.applyTo = applyTo;
+    }
+
+    @Override
+    public <T> T reduce(Reducer<T> reducer) {
+        Object reducedChild = applyTo.reduce(reducer);
+        if (reducedChild == null) return null;
+        return reducer.reduceNode(this, reducedChild);
+    }
+
+    /**
+     * Gets the operation of this node.
+     *
+     * @return the operation this node performs.
+     */
+    public String getOperation() {
+        return operation;
+    }
+
+    /**
+     * Gets the node to which this node's operation applies.
+     *
+     * @return the tree node to which the operation will be applied.
+     */
+    public TreeNode getApplyTo() {
+        return applyTo;
+    }
+
+    @Override
+    public String toString() {
+        return "(" + (applyTo == null ? "null" : applyTo.toString()) + ")" + operation;
+    }
+}

src/main/kotlin/org/nwapw/abacus/function/Documentation.kt

@@ -1,26 +0,0 @@
-package org.nwapw.abacus.function
-
-/**
- * A data class used for storing information about a function.
- *
- * The Documentation class holds the information necessary to display the information
- * about a function to the user.
- *
- * @param codeName the name of the function as it occurs in code.
- * @param name the name of the function in English.
- * @param description the short description of this function.
- * @param longDescription the full description of this function.
- * @param type the things this documentation maps to.
- */
-data class Documentation(val codeName: String, val name: String,
-                         val description: String, val longDescription: String,
-                         val type: DocumentationType) {
-
-    fun matches(other: String): Boolean {
-        return codeName.toLowerCase().contains(other.toLowerCase()) ||
-                name.toLowerCase().contains(other.toLowerCase()) ||
-                description.toLowerCase().contains(other.toLowerCase()) ||
-                longDescription.toLowerCase().contains(other.toLowerCase())
-    }
-
-}

src/main/kotlin/org/nwapw/abacus/function/Operator.kt

@@ -1,14 +0,0 @@
-package org.nwapw.abacus.function
-
-/**
- * A single operator that can be used by Abacus.
- *
- * This is a data class that holds the information about a single operator, such as a plus or minus.
- *
- * @param associativity the associativity of this operator, used for order of operations;.
- * @param type the type of this operator, used for parsing (infix / prefix / postfix and binary / unary)
- * @param precedence the precedence of this operator, used for order of operations.
- * @param function the function this operator applies to its arguments.
- */
-data class Operator(val associativity: OperatorAssociativity, val type: OperatorType,
-                    val precedence: Int, val function: Function)

src/main/kotlin/org/nwapw/abacus/tree/BinaryNode.kt

@@ -1,26 +0,0 @@
-package org.nwapw.abacus.tree
-
-/**
- * A tree node that holds a binary operation.
- *
- * This node represents any binary operation, such as binary infix or binary postfix. The only
- * currently implemented into Abacus is binary infix, but that has more to do with the parser than
- * this class, which doesn't care about the order that its operation and nodes were found in text.
- *
- * @param operation the operation this node performs on its children.
- * @param left the left node.
- * @param right the right node.
- */
-data class BinaryNode(val operation: String, val left: TreeNode? = null, val right: TreeNode?) : TreeNode() {
-
-    override fun <T : Any> reduce(reducer: Reducer<T>): T? {
-        val leftReduce = left?.reduce(reducer) ?: return null
-        val rightReduce = right?.reduce(reducer) ?: return null
-        return reducer.reduceNode(this, leftReduce, rightReduce)
-    }
-
-    override fun toString(): String {
-        return "(" + (left?.toString() ?: "null") + operation + (right?.toString() ?: "null") + ")"
-    }
-
-}

src/main/kotlin/org/nwapw/abacus/tree/FunctionNode.kt

@@ -1,52 +0,0 @@
-package org.nwapw.abacus.tree
-
-/**
- * A tree node that holds a function call.
- *
- * The function call node can hold any number of children, and passes the to the appropriate reducer,
- * but that is its sole purpose.
- *
- * @param function the function string.
- */
-data class FunctionNode(val function: String) : TreeNode() {
-
-    /**
-     * List of function parameters added to this node.
-     */
-    val children: MutableList<TreeNode> = mutableListOf()
-
-    override fun <T : Any> reduce(reducer: Reducer<T>): T? {
-        val children = Array<Any?>(children.size, { children[it].reduce(reducer) ?: return null; })
-        return reducer.reduceNode(this, *children)
-    }
-
-    override fun toString(): String {
-        val buffer = StringBuffer()
-        buffer.append(function)
-        buffer.append('(')
-        for (i in 0 until children.size) {
-            buffer.append(children[i].toString())
-            buffer.append(if (i == children.size - 1) ")" else ",")
-        }
-        return buffer.toString()
-    }
-
-    /**
-     * Appends a child to this node's list of children.
-     *
-     * @node the node to append.
-     */
-    fun appendChild(node: TreeNode){
-        children.add(node)
-    }
-
-    /**
-     * Prepends a child to this node's list of children.
-     *
-     * @node the node to prepend.
-     */
-    fun prependChild(node: TreeNode){
-        children.add(0, node)
-    }
-
-}

src/main/kotlin/org/nwapw/abacus/tree/NumberNode.kt

@@ -1,23 +0,0 @@
-package org.nwapw.abacus.tree
-
-import org.nwapw.abacus.number.NumberInterface
-
-/**
- * A tree node that holds a single number value.
- *
- * This is a tree node that holds a single NumberInterface, which represents any number,
- * and is not defined during compile time.
- *
- * @number the number value of this node.
- */
-data class NumberNode(val number: NumberInterface) : TreeNode() {
-
-    override fun <T : Any> reduce(reducer: Reducer<T>): T? {
-        return reducer.reduceNode(this)
-    }
-
-    override fun toString(): String {
-        return number.toString()
-    }
-
-}

src/main/kotlin/org/nwapw/abacus/tree/TreeNode.kt

@@ -1,10 +0,0 @@
-package org.nwapw.abacus.tree
-
-/**
- * A tree node.
- */
-abstract class TreeNode {
-
-    abstract fun <T: Any> reduce(reducer: Reducer<T>) : T?
-
-}

src/main/kotlin/org/nwapw/abacus/tree/UnaryNode.kt

@@ -1,23 +0,0 @@
-package org.nwapw.abacus.tree
-
-/**
- * A tree node that holds a unary operation.
- *
- * This node holds a single operator applied to a single parameter, and does not care
- * whether the operation was found before or after the parameter in the text.
- *
- * @param operation the operation applied to the given node.
- * @param applyTo the node to which the operation will be applied.
- */
-data class UnaryNode(val operation: String, val applyTo: TreeNode? = null) : TreeNode() {
-
-    override fun <T : Any> reduce(reducer: Reducer<T>): T? {
-        val reducedChild = applyTo?.reduce(reducer) ?: return null
-        return reducer.reduceNode(this, reducedChild)
-    }
-
-    override fun toString(): String {
-        return "(" + (applyTo?.toString() ?: "null") + ")" + operation
-    }
-
-}

src/main/resources/abacus.fxml

@@ -60,15 +60,6 @@
                     </FlowPane>
                 </GridPane>
             </Tab>
-            <Tab fx:id="functionListTab" text="Functions" closable="false">
-                <VBox spacing="10">
-                    <padding>
-                        <Insets left="10" right="10" top="10" bottom="10"/>
-                    </padding>
-                    <TextField fx:id="functionListSearchField" maxWidth="Infinity"/>
-                    <ListView maxWidth="Infinity" fx:id="functionListView"/>
-                </VBox>
-            </Tab>
         </TabPane>
     </center>
 

src/test/java/org/nwapw/abacus/tests/CalculationTests.java

@@ -88,8 +88,8 @@ public class CalculationTests {
     public void testExp(){
         testOutput("exp0", "exp(0)", "1");
         testOutput("exp1", "exp(1)", "2.718281828459045235360287471352662497757247");
-        testOutput("exp300", "exp(300)", "19424263952412559365842088360176992193662086");
+        testOutput("exp300", "exp(300)", "1.9424263952412559365842088360176992193662086");
-        testOutput("exp300", "exp(300)", "19424263952412559365842088360176992193662086");
+        testOutput("exp(-500)", "exp((500)`)", "7.1245764067412855315491573771227552469277568");
     }
 
     @Test
@@ -99,6 +99,9 @@ public class CalculationTests {
         testOutput("2^1", "(2^1)", "2");
         testOutput("2^-1", "(2^(1)`)", "0.5");
         testOutput("2^50", "(2^50)", "112589990684262");
+        testOutput("7^(-sqrt2*17)", "(7^((sqrt(2)*17))`)", "4.81354609155297814551845300063563");
+        testEvalError("0^0", "(0^0)");
+        testEvalError("(-13)^.9999", "((13)`^0.9999)");
     }
 
 }