Calculating with large floats

LargeFloat.java

@@ -0,0 +1,128 @@
+package rsn170330.lp1;
+
+/**
+ * This class is for calculation with large float numbers.
+ * @author janne
+ *
+ */
+public class LargeFloat {
+
+	/**
+	 * Subtracts two float numbers.
+	 * @param nr1
+	 * @param nr2
+	 * @return result
+	 */
+	public String subFloat(String nr1, String nr2) {
+		String[] arrNr1 = split(nr1);
+		String[] arrNr2 = split(nr2);
+		// Brings the decimal places to the same length.
+		if (!(arrNr1[1].length() == arrNr2[1].length())) {
+			if (arrNr1[1].length() < arrNr2[1].length()) {
+				while (arrNr1[1].length() <= arrNr2[1].length()) {
+					arrNr1[1] = arrNr1[1] + "0";
+				}
+			} else {
+				while (arrNr1[1].length() >= arrNr2[1].length()) {
+					arrNr2[1] = arrNr2[1] + "0";
+				}
+			}
+		}//------------------------------------------------
+		Num mainNr = Num.subtract(new Num(arrNr1[0]), new Num(arrNr2[0]));
+		int len = arrNr1[1].length();
+		Num afterPoint = Num.subtract(new Num(arrNr1[1]), new Num(arrNr2[1]));
+		if (afterPoint.toString().length() > len) {
+			mainNr = Num.subtract(mainNr, new Num("1"));
+			afterPoint = fooNextAfterPoint(afterPoint);
+		}
+		return (mainNr.toString() + "." + afterPoint.toString());
+	}
+
+	/**
+	 * Adds two float numbers.
+	 * @param nr1
+	 * @param nr2
+	 * @return result
+	 */
+	public String addFloat(String nr1, String nr2) {
+		String[] arrNr1 = split(nr1);
+		String[] arrNr2 = split(nr2);
+		// Brings the decimal places to the same length.
+		if (!(arrNr1[1].length() == arrNr2[1].length())) {
+			if (arrNr1[1].length() < arrNr2[1].length()) {
+				while (arrNr1[1].length() <= arrNr2[1].length()) {
+					arrNr1[1] = arrNr1[1] + "0";
+				}
+			} else {
+				while (arrNr1[1].length() >= arrNr2[1].length()) {
+					arrNr2[1] = arrNr2[1] + "0";
+				}
+			}
+		}
+		//------------------------------------------------
+		Num mainNr = Num.add(new Num(arrNr1[0]), new Num(arrNr2[0]));
+		int len = arrNr1[1].length();
+		Num afterPoint = Num.add(new Num(arrNr1[1]), new Num(arrNr2[1]));
+		if (afterPoint.toString().length() > len) {
+			mainNr = Num.add(mainNr, new Num("1"));
+			afterPoint = fooNextAfterPoint(afterPoint);
+		}
+		return (mainNr.toString() + "." + afterPoint.toString());
+	}
+
+	/**
+	 * 
+	 * @param str 111.222
+	 * @return ["111", "222"]
+	 */
+	private String[] split(String str) {
+		char DELIMITER = '.';
+		String[] arr = new String[2];
+		int d = str.indexOf(DELIMITER);
+		char[] vorn = new char[d];
+		char[] hint = new char[str.length() - d - 1];
+		int co = 0;
+		for (int i = 0; i < vorn.length; i++) {
+			vorn[i] = str.charAt(co);
+			co++;
+		}
+		co++;
+		for (int k = 0; k < hint.length; k++) {
+			hint[k] = str.charAt(co);
+			co++;
+		}
+		arr[0] = new String(vorn);
+		arr[1] = new String(hint);
+		return arr;
+	}
+
+	/**
+	 * 
+	 * @param afterPoint 1234
+	 * @return 234
+	 */
+	private Num fooNextAfterPoint(Num afterPoint) {
+		return (new Num(afterPoint.toString().substring(1)));
+	}
+
+	/**
+	 * 
+	 * Test for this class
+	 */
+	public static void main(String[] args) {
+		String float1 = "23456234875623875628376548734.91232452345346573648756348753273589999";
+		String float2 = "5234523453222.777346875634765723650000001111111010101476837658375875647534856387487448567468757777777";
+		LargeFloat largeFloat = new LargeFloat();
+		String result = largeFloat.addFloat(float1, float2);
+		System.out.println("add:" + result);
+		result = largeFloat.subFloat(float2, float1);
+		System.out.println("sub:" + result);
+		System.out.println("Is 2 smaller than 5 " + Num.isSmallerThan(new Num(2), new Num(5)));
+		System.out.println("Is 777773453452344523465453425234532450000000000000000545435245454343549994579878673985769873965876938476897345897960000000000000000000000000000000000000000000000 \n"
+				+ "smaller than 34675687263875672364587647567638472687465897326874658723648756239874658723645876234975628946598236 "
+		+ Num.isSmallerThan(new Num("777773453452344523465453425234532450000000000000000545435245454343549994579878673985769873965876938476897345897960000000000000000000000000000000000000000000000"),
+				new Num("34675687263875672364587647567638472687465897326874658723648756239874658723645876234975628946598236")));
+		Num n = Num.faculty(new Num(8));
+		System.out.println("faculty of 8 is: " + n.toString());
+	}
+}

Num.java

@@ -1,5 +1,4 @@
 package rsn170330.lp1;
-
 /**
  * CS 5V81.001. Implementation of data structures and algorithms 
  * Long Project LP1: Integer arithmetic with arbitrarily large numbers
@@ -189,6 +188,33 @@ else if (!a.isNegative && !b.isNegative) {
 		}
 		return out;
 	}
+
+	/**
+	 * 
+	 * @param a the input number
+	 * @param b the input number
+	 * @return true if a < b
+	 */
+	public static boolean isSmallerThan(Num a, Num b) {
+		Num erg = Num.subtract(b, a);
+		if (erg.toString().charAt(0) == '-') {
+			return false;
+		} else {
+			return true;
+		}
+	}
+
+	/**
+	 * @param from 12
+	 * @return 479001600
+	 */
+	public static Num faculty(Num from) {
+		  Num nr = new Num("1");
+		  for (Num i = new Num("2"); Num.isSmallerThan(i, from); i = Num.add(i, new Num(1))) {
+		      nr = Num.product(nr, i);
+		  }
+		  return nr;
+	}
 
 	/**
 	 * Unsigned addition of two numbers Num a and Num b.
@@ -1231,6 +1257,7 @@ else if (uniqueOperators.get(expr[i]) < uniqueOperators.get(operator.peek()))
 	 * Perform the required Arithmetic operations s1-operator-s2
 	 * And operator must be binary, like +,-,*,/,%,^ 
 	 */
+	@SuppressWarnings("removal")
 	private Num evaluate(String s1, String s2, String operator) {
 
 		Num result = null, num1 = null, num2 = null;

TestLP1.java

@@ -1,5 +1,4 @@
 package rsn170330.lp1;
-
 /* Test program for LP1.
    Usage:  There are 7 tests:
 	java -Xss512m -Xms2g TestLP1 0
@@ -13,6 +12,17 @@
 
 public class TestLP1 {
 	public static void main(String[] args) throws Exception {
+		// githubTest(args);
+		Num x = Num.add(new Num("1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"
+				+ "00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"
+				+ "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"
+				+ "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"
+				+ "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"
+				+ "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"), new Num("4"));
+		System.out.println(x.toString());
+	}
+
+	private static void githubTest(String[] args) {
 		int val = 1;
 		if (args.length > 0) {
 			val = Integer.parseInt(args[0]);