Add the list of number interface providers to Plugins.

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

@@ -1,7 +1,6 @@
 package org.nwapw.abacus;
 
-import org.nwapw.abacus.config.Configuration;
+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;
@@ -46,7 +47,7 @@ public class Abacus {
     /**
      * The configuration loaded from a file.
      */
-    private Configuration configuration;
+    private ConfigurationObject configuration;
     /**
      * The tree builder used to construct a tree
      * from a string.
@@ -59,8 +60,8 @@ public class Abacus {
     public Abacus() {
         pluginManager = new PluginManager();
         numberReducer = new NumberReducer(this);
-        configuration = new Configuration(CONFIG_FILE);
+        configuration = new ConfigurationObject(CONFIG_FILE);
-        configuration.saveTo(CONFIG_FILE);
+        configuration.save(CONFIG_FILE);
         LexerTokenizer lexerTokenizer = new LexerTokenizer();
         ShuntingYardParser shuntingYardParser = new ShuntingYardParser(this);
         treeBuilder = new TreeBuilder<>(lexerTokenizer, shuntingYardParser);
@@ -78,7 +79,13 @@ 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);
     }
 
     /**
@@ -114,7 +121,7 @@ public class Abacus {
      *
      * @return the configuration object.
      */
-    public Configuration getConfiguration() {
+    public ConfigurationObject getConfiguration() {
         return configuration;
     }
 

src/main/java/org/nwapw/abacus/config/Configuration.java

@@ -1,83 +1,14 @@
 package org.nwapw.abacus.config;
 
-import com.moandjiezana.toml.Toml;
-import com.moandjiezana.toml.TomlWriter;
-
-import java.io.File;
-import java.io.IOException;
-
 /**
- * The configuration object that stores
+ * Serializable class that will be used to load TOML
- * options that the user can change.
+ * configurations.
  */
 public class Configuration {
 
     /**
-     * The TOML writer used to write this configuration to a file.
+     * The type of number this calculator should use.
      */
-    private static final TomlWriter TOML_WRITER = new TomlWriter();
+    public String numberType;
-    /**
-     * The TOML reader used to load this config from a file.
-     */
-    private static final Toml TOML_READER = new Toml();
 
-    /**
-     * The implementation of the number that should be used.
-     */
-    private String numberImplementation = "naive";
-
-    /**
-     * Creates a new configuration with the given values.
-     * @param numberImplementation the number implementation, like "naive" or "precise"
-     */
-    public Configuration(String numberImplementation){
-        this.numberImplementation = numberImplementation;
-    }
-
-    /**
-     * Loads a configuration from a given file, keeping non-specified fields default.
-     * @param fromFile the file to load from.
-     */
-    public Configuration(File fromFile){
-        if(!fromFile.exists()) return;
-        copyFrom(TOML_READER.read(fromFile).to(Configuration.class));
-    }
-
-    /**
-     * Copies the values from the given configuration into this one.
-     * @param otherConfiguration the configuration to copy from.
-     */
-    public void copyFrom(Configuration otherConfiguration){
-        this.numberImplementation = otherConfiguration.numberImplementation;
-    }
-
-    /**
-     * Saves this configuration to the given file, creating
-     * any directories that do not exist.
-     * @param file the file to save to.
-     */
-    public void saveTo(File file){
-        if(file.getParentFile() != null) file.getParentFile().mkdirs();
-        try {
-            TOML_WRITER.write(this, file);
-        } catch (IOException e) {
-            e.printStackTrace();
-        }
-    }
-
-    /**
-     * Gets the number implementation from this configuration.
-     * @return the number implementation.
-     */
-    public String getNumberImplementation() {
-        return numberImplementation;
-    }
-
-    /**
-     * Sets the number implementation for the configuration
-     * @param numberImplementation the number implementation.
-     */
-    public void setNumberImplementation(String numberImplementation) {
-        this.numberImplementation = numberImplementation;
-    }
 }

src/main/java/org/nwapw/abacus/config/ConfigurationObject.java

@@ -0,0 +1,111 @@
+package org.nwapw.abacus.config;
+
+import com.moandjiezana.toml.Toml;
+import com.moandjiezana.toml.TomlWriter;
+
+import java.io.File;
+import java.io.IOException;
+
+/**
+ * A configuration object, which essentially
+ * manages saving, loading, and getting values
+ * from the configuration. While Configuration is
+ * the data model, this is the interface with it.
+ */
+public class ConfigurationObject {
+
+    /**
+     * The writer used to store the configuration.
+     */
+    private static final TomlWriter TOML_WRITER = new TomlWriter();
+    /**
+     * The configuration instance being modeled.
+     */
+    private Configuration configuration;
+
+    /**
+     * Creates a new configuration object with the given config.
+     *
+     * @param config the config to use.
+     */
+    public ConfigurationObject(Configuration config) {
+        setup(config);
+    }
+
+    /**
+     * Create a configuration object by attempting to
+     * load a config from the given path, using the
+     * default configuration otherwise.
+     *
+     * @param path the path to attempt to load.
+     */
+    public ConfigurationObject(File path) {
+        Configuration config;
+        if (!path.exists()) {
+            config = getDefaultConfig();
+        } else {
+            Toml parse = new Toml();
+            parse.read(path);
+            config = parse.to(Configuration.class);
+        }
+        setup(config);
+    }
+
+    /**
+     * Creates a new configuration object with the
+     * default configuration.
+     */
+    public ConfigurationObject() {
+        setup(getDefaultConfig());
+    }
+
+    /**
+     * Sets up the ConfigurationObject.
+     * different constructors do different things,
+     * but they all lead here.
+     *
+     * @param configuration the configuration to set up with.
+     */
+    private void setup(Configuration configuration) {
+        this.configuration = configuration;
+    }
+
+    /**
+     * Creates a default configuration.
+     *
+     * @return the newly created default configuration.
+     */
+    private Configuration getDefaultConfig() {
+        configuration = new Configuration();
+        configuration.numberType = "naive";
+        return configuration;
+    }
+
+    /**
+     * Returns the implementation the user has requested to
+     * represent their numbers.
+     *
+     * @return the implementation name.
+     */
+    public String getNumberImplementation() {
+        return configuration.numberType;
+    }
+
+    /**
+     * Saves the ConfigurationObject to the given file.
+     *
+     * @param toFile the file to save ot.
+     * @return true if the save succeed, false if otherwise.
+     */
+    public boolean save(File toFile) {
+        if (toFile.getParentFile() != null) toFile.getParentFile().mkdirs();
+        try {
+            TOML_WRITER.write(configuration, toFile);
+            return true;
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+        return false;
+    }
+
+}

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

@@ -4,5 +4,5 @@ package org.nwapw.abacus.function;
  * The type of an operator, describing how it should behave.
  */
 public enum OperatorType {
-    BINARY_INFIX, UNARY_POSTFIX, UNARY_PREFIX
+    BINARY_INFIX, UNARY_POSTFIX
 }

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

@@ -1,110 +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;
-    @FXML
-    private ComboBox<String> numberImplementationBox;
-
-    /**
-     * 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 ObservableList<String> numberImplementationOptions;
-
-    private Abacus abacus;
-
-    @FXML
-    public void initialize(){
-        Callback<TableColumn<HistoryModel, String>, TableCell<HistoryModel, String>> cellFactory =
-                param -> new CopyableCell<>();
-
-        historyData = FXCollections.observableArrayList();
-        historyTable.setItems(historyData);
-        numberImplementationOptions = FXCollections.observableArrayList();
-        numberImplementationBox.setItems(numberImplementationOptions);
-        numberImplementationBox.valueProperty().addListener((observable, oldValue, newValue)
-                -> {
-            abacus.getConfiguration().setNumberImplementation(newValue);
-            abacus.getConfiguration().saveTo(Abacus.CONFIG_FILE);
-        });
-        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());
-
-        abacus = new Abacus();
-        numberImplementationOptions.addAll(abacus.getPluginManager().getAllNumbers());
-        String actualImplementation = abacus.getConfiguration().getNumberImplementation();
-        String toSelect = (numberImplementationOptions.contains(actualImplementation)) ? actualImplementation : "naive";
-        numberImplementationBox.getSelectionModel().select(toSelect);
-    }
-
-    @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/NaiveNumber.java

@@ -94,8 +94,23 @@ public class NaiveNumber implements NumberInterface {
     }
 
     @Override
-    public int ceiling() {
+    public NumberInterface ceiling() {
-        return (int) Math.ceil(value);
+        return new NaiveNumber(Math.ceil(value));
+    }
+
+    @Override
+    public NumberInterface floor() {
+        return new NaiveNumber(Math.floor(value));
+    }
+
+    @Override
+    public NumberInterface fractionalPart() {
+        return new NaiveNumber(value - Math.floor(value));
+    }
+
+    @Override
+    public int intValue() {
+        return (int)value;
     }
 
     @Override

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

@@ -83,7 +83,26 @@ public interface NumberInterface {
      * 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();
+    NumberInterface ceiling();
+
+    /**
+     * Return the greatest integer less than or equal to the number.
+     * @return the greatest int >= the number, if int can hold the value.
+     */
+    NumberInterface floor();
+
+    /**
+     * Returns the fractional part of the number.
+     * @return the fractional part of the number.
+     */
+    NumberInterface fractionalPart();
+
+    /**
+     * Returns the integer representation of this number, discarding any fractional part,
+     * if int can hold the value.
+     * @return
+     */
+    int intValue();
 
     /**
      * Promotes this class to another number class.

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

@@ -1,12 +1,9 @@
 package org.nwapw.abacus.number;
 
 import java.math.BigDecimal;
+import java.math.MathContext;
 import java.math.RoundingMode;
 
-/**
- * A number that uses a BigDecimal to store its value,
- * leading to infinite possible precision.
- */
 public class PreciseNumber implements NumberInterface {
 
     /**
@@ -99,8 +96,38 @@ public class PreciseNumber implements NumberInterface {
     }
 
     @Override
-    public int ceiling() {
+    public NumberInterface ceiling() {
-        return (int) Math.ceil(value.doubleValue());
+        String str = value.toPlainString();
+        int decimalIndex = str.indexOf('.');
+        if(decimalIndex != -1){
+            return this.floor().add(ONE);
+        }
+        return this;
+    }
+
+    @Override
+    public NumberInterface floor() {
+        String str = value.toPlainString();
+        int decimalIndex = str.indexOf('.');
+        if(decimalIndex != -1){
+            return new PreciseNumber(str.substring(0, decimalIndex));
+        }
+        return this;
+    }
+
+    @Override
+    public NumberInterface fractionalPart() {
+        String str = value.toPlainString();
+        int decimalIndex = str.indexOf('.');
+        if(decimalIndex != -1){
+            return new PreciseNumber(str.substring(decimalIndex + 1));
+        }
+        return ZERO;
+    }
+
+    @Override
+    public int intValue() {
+        return value.intValue();
     }
 
     @Override

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

@@ -55,12 +55,9 @@ public class ShuntingYardParser implements Parser<Match<TokenType>>, PluginListe
     public List<Match<TokenType>> intoPostfix(List<Match<TokenType>> from) {
         ArrayList<Match<TokenType>> output = new ArrayList<>();
         Stack<Match<TokenType>> tokenStack = new Stack<>();
-        TokenType previousType;
-        TokenType matchType = null;
         while (!from.isEmpty()) {
             Match<TokenType> match = from.remove(0);
-            previousType = matchType;
+            TokenType matchType = match.getType();
-            matchType = match.getType();
             if (matchType == TokenType.NUM) {
                 output.add(match);
             } else if (matchType == TokenType.FUNCTION) {
@@ -77,13 +74,7 @@ public class ShuntingYardParser implements Parser<Match<TokenType>>, PluginListe
                     continue;
                 }
 
-                if(tokenString.equals("-") && (previousType == null || previousType == TokenType.OP ||
+                while (!tokenStack.empty()) {
-                        previousType == TokenType.OPEN_PARENTH)){
-                    from.add(0, new Match<>("`", TokenType.OP));
-                    continue;
-                }
-
-                while (!tokenStack.empty() && type == OperatorType.BINARY_INFIX) {
                     Match<TokenType> otherMatch = tokenStack.peek();
                     TokenType otherMatchType = otherMatch.getType();
                     if (!(otherMatchType == TokenType.OP || otherMatchType == TokenType.FUNCTION)) break;
@@ -112,8 +103,8 @@ public class ShuntingYardParser implements Parser<Match<TokenType>>, PluginListe
         }
         while (!tokenStack.empty()) {
             Match<TokenType> match = tokenStack.peek();
-            TokenType newMatchType = match.getType();
+            TokenType matchType = match.getType();
-            if (!(newMatchType == TokenType.OP || newMatchType == TokenType.FUNCTION)) return null;
+            if (!(matchType == TokenType.OP || matchType == TokenType.FUNCTION)) return null;
             output.add(tokenStack.pop());
         }
         return output;
@@ -136,11 +127,11 @@ public class ShuntingYardParser implements Parser<Match<TokenType>>, PluginListe
                 TreeNode right = constructRecursive(matches);
                 TreeNode left = constructRecursive(matches);
                 if (left == null || right == null) return null;
-                else return new BinaryNode(operator, left, right);
+                else return new BinaryInfixNode(operator, left, right);
             } else {
                 TreeNode applyTo = constructRecursive(matches);
                 if (applyTo == null) return null;
-                else return new UnaryNode(operator, applyTo);
+                else return new UnaryPrefixNode(operator, applyTo);
             }
         } else if (matchType == TokenType.NUM) {
             return new NumberNode(abacus.numberFromString(match.getContent()));

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

@@ -29,6 +29,10 @@ public abstract class Plugin {
      * A hash map of operators mapped to their string names.
      */
     private Map<String, Class<? extends NumberInterface>> numbers;
+    /**
+     * A hash map of constant providers for each number type.
+     */
+    private Map<Class<?>, java.util.function.Function<String, NumberInterface>> constantProviders;
     /**
      * The plugin manager in which to search for functions
      * not inside this package,
@@ -52,6 +56,7 @@ public abstract class Plugin {
         functions = new HashMap<>();
         operators = new HashMap<>();
         numbers = new HashMap<>();
+        constantProviders = new HashMap<>();
         enabled = false;
     }
 
@@ -82,6 +87,14 @@ public abstract class Plugin {
         return numbers.keySet();
     }
 
+    /**
+     * Gets the list of all constant providers provided by this plugin.
+     * @return the list of constant providers.
+     */
+    public final Set<Class<?>> providedConstantProviders() {
+        return constantProviders.keySet();
+    }
+
     /**
      * Gets a function under the given function name.
      *
@@ -112,6 +125,16 @@ public abstract class Plugin {
         return numbers.get(numberName);
     }
 
+    /**
+     * Gets the constant provider for the given class.
+     *
+     * @param pluginClass the class for which to provide constants.
+     * @return the provider, or null, if the plugin doesn't provide it.
+     */
+    public final java.util.function.Function<String, NumberInterface> getConstantProvider(Class<?> pluginClass){
+        return constantProviders.get(pluginClass);
+    }
+
     /**
      * Enables the function, loading the necessary instances
      * of functions.
@@ -131,6 +154,8 @@ public abstract class Plugin {
         onDisable();
         functions.clear();
         operators.clear();
+        numbers.clear();
+        constantProviders.clear();
         enabled = false;
     }
 
@@ -170,6 +195,19 @@ public abstract class Plugin {
         numbers.put(name, toRegister);
     }
 
+    /**
+     * To be used in load(). Registers a constant provider
+     * with the plugin internally, which makes it possible
+     * for the calculations to look up constants for each different
+     * number type.
+     * @param providerFor the class the provider works with.
+     * @param constantProvider the provider to register.
+     */
+    protected final void registerConstantProvider(Class<?> providerFor,
+                                                   java.util.function.Function<String, NumberInterface> constantProvider) {
+        constantProviders.put(providerFor, constantProvider);
+    }
+
     /**
      * Searches the PluginManager for the given function name.
      * This can be used by the plugins internally in order to call functions
@@ -194,6 +232,30 @@ public abstract class Plugin {
         return manager.operatorFor(name);
     }
 
+    /**
+     * Searches the PluginManager for the given number implementation.
+     * This can be used by the plugins internally in order to
+     * find classes by name that they do not provide.
+     *
+     * @param name the name for which to search
+     * @return the resulting number class.
+     */
+    protected final Class<? extends NumberInterface> numberFor(String name) {
+        return manager.numberFor(name);
+    }
+
+    /**
+     * Searches the PluginManager for the given constant provider.
+     * This can be used by the plugins internally in order
+     * to find constant providers for number provider they do not provide.
+     *
+     * @param forClass the class for which to get a generator for.
+     * @return the resulting generator
+     */
+    protected final java.util.function.Function<String, NumberInterface> constantProviderFor(Class<?> forClass){
+        return manager.constantProviderFor(forClass);
+    }
+
     /**
      * Abstract method to be overridden by plugin implementation, in which the plugins
      * are supposed to register the functions they provide and do any other

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

@@ -36,6 +36,11 @@ public class PluginManager {
      * been cached, that is, found in a plugin and returned.
      */
     private Map<String, Class<? extends NumberInterface>> cachedNumbers;
+    /**
+     * List of registered constant providers for every
+     * number class.
+     */
+    private Map<Class<?>, java.util.function.Function<String, NumberInterface>> cachedConstantProviders;
     /**
      * List of all functions loaded by the plugins.
      */
@@ -48,6 +53,10 @@ public class PluginManager {
      * List of all numbers loaded by the plugins.
      */
     private Set<String> allNumbers;
+    /**
+     * List of all the constant providers loaded by the plugins.
+     */
+    private Set<Class<?>> allConstantProviders;
     /**
      * The list of plugin listeners attached to this instance.
      */
@@ -62,9 +71,11 @@ public class PluginManager {
         cachedFunctions = new HashMap<>();
         cachedOperators = new HashMap<>();
         cachedNumbers = new HashMap<>();
+        cachedConstantProviders = new HashMap<>();
         allFunctions = new HashSet<>();
         allOperators = new HashSet<>();
         allNumbers = new HashSet<>();
+        allConstantProviders = new HashSet<>();
         listeners = new HashSet<>();
     }
 
@@ -80,12 +91,13 @@ public class PluginManager {
      * @param getFunction the function to get the T value under the given name
      * @param name        the name to search for
      * @param <T>         the type of element being search
+     * @param <K>         the type of key that the cache is indexed by.
      * @return the retrieved element, or null if it was not found.
      */
-    private static <T> T searchCached(Collection<Plugin> plugins, Map<String, T> cache,
+    private static <T, K> T searchCached(Collection<Plugin> plugins, Map<K, T> cache,
-                                      java.util.function.Function<Plugin, Set<String>> setFunction,
+                                      java.util.function.Function<Plugin, Set<K>> setFunction,
-                                      java.util.function.BiFunction<Plugin, String, T> getFunction,
+                                      java.util.function.BiFunction<Plugin, K, T> getFunction,
-                                      String name) {
+                                      K name) {
         if (cache.containsKey(name)) return cache.get(name);
 
         T loadedValue = null;
@@ -130,6 +142,15 @@ public class PluginManager {
         return searchCached(plugins, cachedNumbers, Plugin::providedNumbers, Plugin::getNumber, name);
     }
 
+    /**
+     * Gets the constant provider for the given class.
+     * @param forClass the class to get the provider for.
+     * @return the provider.
+     */
+    public java.util.function.Function<String, NumberInterface> constantProviderFor(Class<?> forClass){
+        return searchCached(plugins, cachedConstantProviders, Plugin::providedConstantProviders, Plugin::getConstantProvider, forClass);
+    }
+
     /**
      * Adds an instance of Plugin that already has been instantiated.
      *
@@ -165,6 +186,7 @@ public class PluginManager {
             allFunctions.addAll(plugin.providedFunctions());
             allOperators.addAll(plugin.providedOperators());
             allNumbers.addAll(plugin.providedNumbers());
+            allConstantProviders.addAll(plugin.providedConstantProviders());
         }
         listeners.forEach(e -> e.onLoad(this));
     }
@@ -177,6 +199,7 @@ public class PluginManager {
         allFunctions.clear();
         allOperators.clear();
         allNumbers.clear();
+        allConstantProviders.clear();
         listeners.forEach(e -> e.onUnload(this));
     }
 
@@ -215,6 +238,14 @@ public class PluginManager {
         return allNumbers;
     }
 
+    /**
+     * Gets all the constant providers loaded by the Plugin Manager.
+     * @return the set of all constant providers that were loaded.
+     */
+    public Set<Class<?>> getAllConstantProviders() {
+        return allConstantProviders;
+    }
+
     /**
      * Adds a plugin change listener to this plugin manager.
      *

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

@@ -8,6 +8,7 @@ import org.nwapw.abacus.number.NaiveNumber;
 import org.nwapw.abacus.number.NumberInterface;
 import org.nwapw.abacus.number.PreciseNumber;
 
+import java.lang.reflect.InvocationTargetException;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.function.BiFunction;
@@ -19,6 +20,7 @@ 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>>();
+    static HashMap<Class<? extends NumberInterface>, NumberInterface> piValues = new HashMap<Class<? extends NumberInterface>, NumberInterface>();
 
     /**
      * The addition operator, +
@@ -52,20 +54,6 @@ public class StandardPlugin extends Plugin {
             return params[0].subtract(params[1]);
         }
     });
-    /**
-     * The negation operator, -
-     */
-    public static final Operator OP_NEGATE = new Operator(OperatorAssociativity.LEFT, OperatorType.UNARY_PREFIX, 0, new Function() {
-        @Override
-        protected boolean matchesParams(NumberInterface[] params) {
-            return params.length == 1;
-        }
-
-        @Override
-        protected NumberInterface applyInternal(NumberInterface[] params) {
-            return params[0].negate();
-        }
-    });
     /**
      * The multiplication operator, *
      */
@@ -186,7 +174,7 @@ public class StandardPlugin extends Plugin {
                 //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;
+                NumberInterface left = params[0].multiply((new NaiveNumber(3)).promoteTo(params[0].getClass()).intPow(params[0].ceiling().intValue())), right = maxError;
                 do{
                     sum = sum.add(nextNumerator.divide(factorial(params[0].getClass(), n+1)));
                     n++;
@@ -294,6 +282,32 @@ public class StandardPlugin extends Plugin {
         }
     };
 
+    /**
+     * The sine function (the argument is interpreted in radians).
+     */
+    public static final Function FUNCTION_SIN = new Function() {
+        @Override
+        protected boolean matchesParams(NumberInterface[] params) {
+            return params.length == 1;
+        }
+
+        @Override
+        protected NumberInterface applyInternal(NumberInterface[] params) {
+            NumberInterface pi = getPi(params[0].getClass());
+            NumberInterface twoPi = pi.multiply(new NaiveNumber(2).promoteTo(pi.getClass()));
+            NumberInterface theta = getSmallAngle(params[0]);
+            //System.out.println(theta);
+            if(theta.compareTo(pi.multiply(new NaiveNumber(1.5).promoteTo(twoPi.getClass()))) >= 0){
+                theta = theta.subtract(twoPi);
+            }
+            else if(theta.compareTo(pi.divide(new NaiveNumber(2).promoteTo(pi.getClass()))) > 0){
+                theta = pi.subtract(theta);
+            }
+            //System.out.println(theta);
+            return sinTaylor(theta);
+        }
+    };
+
     public StandardPlugin(PluginManager manager) {
         super(manager);
     }
@@ -331,7 +345,6 @@ public class StandardPlugin extends Plugin {
 
         registerOperator("+", OP_ADD);
         registerOperator("-", OP_SUBTRACT);
-        registerOperator("`", OP_NEGATE);
         registerOperator("*", OP_MULTIPLY);
         registerOperator("/", OP_DIVIDE);
         registerOperator("^", OP_CARET);
@@ -341,6 +354,7 @@ public class StandardPlugin extends Plugin {
         registerFunction("exp", FUNCTION_EXP);
         registerFunction("ln", FUNCTION_LN);
         registerFunction("sqrt", FUNCTION_SQRT);
+        registerFunction("sin", FUNCTION_SIN);
     }
 
     @Override
@@ -348,9 +362,16 @@ public class StandardPlugin extends Plugin {
 
     }
 
+    /**
+     * A factorial function that uses memoization for each number class; it efficiently
+     * computes factorials of non-negative integers.
+     * @param numberClass type of number to return.
+     * @param n non-negative integer.
+     * @return a number of numClass with value n factorial.
+     */
     public static NumberInterface factorial(Class<? extends NumberInterface> numberClass, int n){
         if(!factorialLists.containsKey(numberClass)){
-            factorialLists.put(numberClass, new ArrayList<>());
+            factorialLists.put(numberClass, new ArrayList<NumberInterface>());
             factorialLists.get(numberClass).add(NaiveNumber.ONE.promoteTo(numberClass));
             factorialLists.get(numberClass).add(NaiveNumber.ONE.promoteTo(numberClass));
         }
@@ -363,4 +384,71 @@ public class StandardPlugin extends Plugin {
         return list.get(n);
     }
 
+    /**
+     * Returns the value of the Taylor series for sin (centered at 0) at x.
+     * @param x where the series is evaluated.
+     * @return the value of the series
+     */
+    private static NumberInterface sinTaylor(NumberInterface x){
+        NumberInterface power = x, multiplier = x.multiply(x).negate(), currentTerm = x, sum = x;
+        NumberInterface maxError = getMaxError(x);
+        int n = 1;
+        do{
+            n += 2;
+            power = power.multiply(multiplier);
+            currentTerm = power.divide(factorial(x.getClass(), n));
+            sum = sum.add(currentTerm);
+        } while (FUNCTION_ABS.apply(currentTerm).compareTo(maxError) > 0);
+        return sum;
+    }
+
+    /**
+     * Returns an approximation of Pi, with appropriate accuracy for given number class.
+     * @param numClass type of number.
+     * @return A number of class numClass, with value approximately Pi = 3.1415...
+     */
+    public static NumberInterface getPi(Class<? extends NumberInterface> numClass){
+        if(!piValues.containsKey(numClass)){
+            //https://en.wikipedia.org/wiki/Chudnovsky_algorithm
+            NumberInterface C = FUNCTION_SQRT.apply(new NaiveNumber(10005).promoteTo(numClass)).multiply(new NaiveNumber(426880).promoteTo(numClass));
+            NumberInterface M = NaiveNumber.ONE.promoteTo(numClass);
+            NumberInterface L = new NaiveNumber(13591409).promoteTo(numClass);
+            NumberInterface X = M;
+            NumberInterface sum = L;
+            int termsNeeded = C.getMaxPrecision()/13 + 1;
+
+            NumberInterface lSummand = new NaiveNumber(545140134).promoteTo(L.getClass());
+            NumberInterface xMultiplier = new NaiveNumber(262537412).promoteTo(X.getClass())
+                    .multiply(new NaiveNumber(1000000000).promoteTo(X.getClass()))
+                    .add(new NaiveNumber(640768000).promoteTo(X.getClass()))
+                    .negate();
+            for(int i = 0; i < termsNeeded; i++){
+                M = M
+                        .multiply(new NaiveNumber(12*i+2).promoteTo(M.getClass()))
+                        .multiply(new NaiveNumber(12*i+6).promoteTo(M.getClass()))
+                        .multiply(new NaiveNumber(12*i+10).promoteTo(M.getClass()))
+                        .divide(new NaiveNumber(Math.pow(i+1,3)).promoteTo(M.getClass()));
+                L = L.add(lSummand);
+                X = X.multiply(xMultiplier);
+                sum = sum.add(M.multiply(L).divide(X));
+            }
+            piValues.put(numClass, C.divide(sum));
+        }
+        return piValues.get(numClass);
+    }
+
+    /**
+     * Returns an equivalent angle in the interval [0, 2pi)
+     * @param phi an angle (in radians).
+     * @return theta in [0, 2pi) that differs from phi by a multiple of 2pi.
+     */
+    private static NumberInterface getSmallAngle(NumberInterface phi){
+        NumberInterface twoPi = getPi(phi.getClass()).multiply(new NaiveNumber("2").promoteTo(phi.getClass()));
+        NumberInterface theta = FUNCTION_ABS.apply(phi).subtract(twoPi
+        .multiply(FUNCTION_ABS.apply(phi).divide(twoPi).floor())); //Now theta is in [0, 2pi).
+        if(phi.signum() < 0){
+            theta = twoPi.subtract(theta);
+        }
+        return theta;
+    }
 }

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

@@ -3,7 +3,7 @@ package org.nwapw.abacus.tree;
 /**
  * A tree node that represents an operation being applied to two operands.
  */
-public class BinaryNode extends TreeNode {
+public class BinaryInfixNode extends TreeNode {
 
     /**
      * The operation being applied.
@@ -18,7 +18,7 @@ public class BinaryNode extends TreeNode {
      */
     private TreeNode right;
 
-    private BinaryNode() {
+    private BinaryInfixNode() {
     }
 
     /**
@@ -27,7 +27,7 @@ public class BinaryNode extends TreeNode {
      *
      * @param operation the operation.
      */
-    public BinaryNode(String operation) {
+    public BinaryInfixNode(String operation) {
         this(operation, null, null);
     }
 
@@ -39,7 +39,7 @@ public class BinaryNode extends TreeNode {
      * @param left      the left node of the expression.
      * @param right     the right node of the expression.
      */
-    public BinaryNode(String operation, TreeNode left, TreeNode right) {
+    public BinaryInfixNode(String operation, TreeNode left, TreeNode right) {
         this.operation = operation;
         this.left = left;
         this.right = right;

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

@@ -28,15 +28,15 @@ public class NumberReducer implements Reducer<NumberInterface> {
     public NumberInterface reduceNode(TreeNode node, Object... children) {
         if (node instanceof NumberNode) {
             return ((NumberNode) node).getNumber();
-        } else if (node instanceof BinaryNode) {
+        } else if (node instanceof BinaryInfixNode) {
             NumberInterface left = (NumberInterface) children[0];
             NumberInterface right = (NumberInterface) children[1];
-            Function function = abacus.getPluginManager().operatorFor(((BinaryNode) node).getOperation()).getFunction();
+            Function function = abacus.getPluginManager().operatorFor(((BinaryInfixNode) node).getOperation()).getFunction();
             if (function == null) return null;
             return function.apply(left, right);
-        } else if (node instanceof UnaryNode) {
+        } else if (node instanceof UnaryPrefixNode) {
             NumberInterface child = (NumberInterface) children[0];
-            Function functionn = abacus.getPluginManager().operatorFor(((UnaryNode) node).getOperation()).getFunction();
+            Function functionn = abacus.getPluginManager().operatorFor(((UnaryPrefixNode) node).getOperation()).getFunction();
             if (functionn == null) return null;
             return functionn.apply(child);
         } else if (node instanceof FunctionNode) {

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

@@ -1,6 +1,6 @@
 package org.nwapw.abacus.tree;
 
-public class UnaryNode extends TreeNode {
+public class UnaryPrefixNode extends TreeNode {
 
     /**
      * The operation this node will apply.
@@ -16,7 +16,7 @@ public class UnaryNode extends TreeNode {
      *
      * @param operation the operation for this node.
      */
-    public UnaryNode(String operation) {
+    public UnaryPrefixNode(String operation) {
         this(operation, null);
     }
 
@@ -26,7 +26,7 @@ public class UnaryNode extends TreeNode {
      * @param operation the operation for this node.
      * @param applyTo   the node to apply the function to.
      */
-    public UnaryNode(String operation, TreeNode applyTo) {
+    public UnaryPrefixNode(String operation, TreeNode applyTo) {
         this.operation = operation;
         this.applyTo = applyTo;
     }

src/main/resources/abacus.fxml

@@ -1,54 +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?>
-<?import javafx.scene.layout.HBox?>
-<?import javafx.scene.layout.GridPane?>
-<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">
-                <GridPane hgap="10" vgap="10">
-                    <padding><Insets left="10" right="10" top="10" bottom="10"/></padding>
-                    <Label text="Number Implementation" GridPane.columnIndex="0" GridPane.rowIndex="0"/>
-                    <ComboBox fx:id="numberImplementationBox" GridPane.columnIndex="1" GridPane.rowIndex="0"/>
-                </GridPane>
-            </Tab>
-        </TabPane>
-    </center>
-
-</BorderPane>