JD1's Personal Development Blog

There are many built in methods we can use to conduct mathematical operations to numbers. Here are some of them.

class Class1{
	public static void main(String args[]){
		//How far number is from zero.
		System.out.println(Math.abs(-26.7));
		//Rounds number up.
		System.out.println(Math.ceil(7.4));
		//Rounds number down.
		System.out.println(Math.floor(7.8));
		//Greater of the two numbers.
		System.out.println(Math.max(8.6,

...

We use the Do While Loop when we want to run a set of instructions before testing to see if a condition is true. The difference between a Do While Loop and a While Loop is that the While Loop tests the condition first and then runs the instructions.

class Class1{
	public static void main(String args[]){
		int counter = 0;
		do{
			System.out.println(counter);
			counter++;
		}while(counter <= 10);
	}
}

...

Compound interest can be calculated with the following formula.

A = Amount
P = Principal
R = Rate
n = Years

A=P(1+R)^n

We can calculate the amount in Java as shown below. We currently know the principal (10,000) and the rate (1%). The years can change depending on how much information we want. In this application, we'll just use 20.

class Class1{
	public static void main(String args[]){
		double amount;

...

The For Loop is probably the most common loop used in any programming language. Here's how it works in Java.

class Class1{
	public static void main(String args[]){
		for(int counter=1; counter<=10; counter++){
			System.out.println(counter);
		}
	}
}

The For Loop takes three arguments: where you want it to start, where you want it to end, and how you'd like to increment the counter. Take a look at the below ...

What this application does is collects a number of inputs from the user via a scanner. These inputs are numbers. They are then averaged and the average is outputted. Pretty simple stuff.

import java.util.Scanner;
class Class1{
	public static void main(String args[]){
		Scanner input = new Scanner(System.in);
		int total = 0;
		int grade;
		int average;
		int counter = 0;
		int numGrades = 10;
 
		System.out.println("Please

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