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SimoneChimirriSimoneChimirri
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ch07p2
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‎ch05/GuessStarterRecursive.java‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -25,7 +25,7 @@ public static void main(String[] args) {
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}
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/**
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* This method prompt the user for his guess,
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* This method prompts the user for his guess,
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* gets the value and tells him if it was too high or too low.
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* @param random the random generated number to guess
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*/

‎ch06/Exercise6.java‎

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Original file line numberDiff line numberDiff line change
@@ -66,7 +66,7 @@ public static int oddSum(int n){
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}
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/**
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* This method calculate the value of the
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* This method calculates the value of the
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* Ackermann function given two non-negative integers
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* @param m the first non-negative integer
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* @param n the second non-negative integer
@@ -86,7 +86,7 @@ public static int ack(int m, int n){
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}
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/**
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* This recursive method calculate
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* This recursive method calculates
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* the value of the power x^n.
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* @param x the base of the power
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* @param n the exponent of the power

‎ch07/Exercise7.java‎

Lines changed: 80 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -7,6 +7,17 @@ public static void main(String[] args) {
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loop(10);
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System.out.println(squareRoot(9.0));
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System.out.println(power(2.0,8));
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System.out.println(factorial(8));
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System.out.println(myexp(8.0,100));
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check(1);
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for(double i=0.1; i<=100.0; i*=10){
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check(i);
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}
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System.out.println("The values of exponential e^x for x=-0.1,-1.0,-10.0,-100.0 are:");
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for(double i=-0.1; i>=-100.0; i*=10){
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System.out.println(myexp(i,100));
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}
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System.out.println(gauss(2.0,100));
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}
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public static void loop(int n) {
@@ -22,7 +33,7 @@ public static void loop(int n) {
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}
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/**
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* This method calculate an approximation
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* This method calculates an approximation
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* of the square root of a number
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* @param a the number whose root will be found
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* @return the approximated result of the square root
@@ -56,7 +67,7 @@ public static double squareRoot(double a){
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}
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/**
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* This method calculate
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* This method calculates
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* the value of the power x^n.
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* @param x the base of the power
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* @param n the exponent of the power
@@ -80,4 +91,71 @@ public static double power(double x, int n) {
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return power;
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}
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/**
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* This method computes the factorial function
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* of a given integer n.
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* @param n the argument of the factorial function
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* @return the value of the factorial function
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*/
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public static int factorial(int n){
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int result = 1;
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for(int i=n;i > 1; i--){
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result *= i;
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}
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return result;
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}
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/**
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* This method calculates e^x
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* using an infinite series expansion,
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* whose i^th term is: x^i/i!.
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* @param x the exponent of the exponential
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* @param n the number of terms of the series
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* we want to add
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* @return the value of the exponential
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*/
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public static double myexp(double x, int n){
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double result = 1;
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double temp = 1;
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for(int i=1; i <= n; i++){
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temp *= x/i;
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result += temp;
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}
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return result;
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}
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/**
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* This method compares the values of the exponential e^x
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* computed ith this class' method 'myexp' and
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* the ones computed with Math.exp(), showing them
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* in different columns.
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* @param x the exponent of the function to calculates
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*/
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public static void check(double x){
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System.out.print(x);
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System.out.print("\t");
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System.out.print(myexp(x,100));
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System.out.print("\t");
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System.out.print(Math.exp(x));
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System.out.println();
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}
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/**
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* This method calculates exp(-x^2),
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* given an integer x, using an
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* infinite series expansion of Gauss.
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* @param x the argument of the exponential
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* @param n the number of terms of the series
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* @return the value of the exponential
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*/
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public static double gauss(double x, int n){
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double result = 1;
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double temp = 1;
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for(int i=1; i<=n; i++){
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temp *= -x*x/i;
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result += temp;
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}
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return result;
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}
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}

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