SINGLE-DIMENSIONAL ARRAYS - Introduction to Java Programming: Comprehensive Version - page 249

myList[ 2 ] = 3.4 ;
myList[ 3 ] = 3.5 ;

Caution
The new operator is not used in the array-initializer syntax. Using an array initializer, you
have to declare, create, and initialize the array all in one statement. Splitting it would
cause a syntax error. Thus, the next statement is wrong:

double [] myList;
myList = { 1.9 , 2.9 , 3.4 , 3.5 };

7.2.6 Processing Arrays
When processing array elements, you will often use a for loop—for two reasons:

All of the elements in an array are of the same type. They are evenly processed in the
same fashion repeatedly using a loop.

■

Since the size of the array is known, it is natural to use a for loop.

■

Assume the array is created as follows:

double [] myList = new double [ 10 ];

The following are some examples of processing arrays.

1. Initializing arrays with input values: The following loop initializes the array myList
with user input values.

java.util.Scanner input = new java.util.Scanner(System.in);
System.out.print( "Enter " + myList.length + " values: " );
for ( int i = 0 ; i < myList.length; i++)
myList[i] = input.nextDouble();

2. Initializing arrays with random values: The following loop initializes the array myList
with random values between 0.0 and 100.0 , but less than 100.0 .

for ( int i = 0 ; i < myList.length; i++) {
myList[i] = Math.random() * 100 ;
}

3. Displaying arrays: To print an array, you have to print each element in the array using a
loop like the following:

for ( int i = 0 ; i < myList.length; i++) {
System.out.print(myList[i] + " " );
}

Tip
For an array of the char[] type, it can be printed using one print statement. For exam-
ple, the following code displays Dallas :

print character array

char [] city = { 'D' , 'a' , 'l' , 'l' , 'a' , 's' };
System.out.println(city);

4. Summing all elements: Use a variable named total to store the sum. Initially total
is 0 . Add each element in the array to total using a loop like this:

double total = 0 ;
for ( int i = 0 ; i < myList.length; i++) {
total += myList[i];
}