created 06/04/03, revised 11/21/15
These exercises create a class,
Weight
that contains an array
of the weight of an individual
taken on successive days
for one month.
Complete the constructor in the following program so that it
constructs the array data
,
then copies values from the parameter init
into data
.
Then complete the toString()
method.
class Weight { private int[] data; // Constructor public Weight(int[] init) { // Make data the same length // as the array referenced by init. data = new .... // Copy values from the // input data to data. for (int j.....) { data[j] = } } //Print public String toString() { } } public class WeightTester { public static void main ( String[] args ) { int[] values = { 98, 99, 98, 99, 100, 101, 102, 100, 104, 105, 105, 106, 105, 103, 104, 103, 105, 106, 107, 106, 105, 105, 104, 104, 103, 102, 102, 101, 100, 102}; Weight june = new Weight( values ); System.out.println( june ); } }
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Now add an average()
method to the class.
Use integer math.
class Weight { . . . public int average() { . . . } } public class WeightTester { public static void main ( String[] args ) { int[] values = { 98, 99, 98, 99, 100, 101, 102, 100, 104, 105, 105, 106, 105, 103, 104, 103, 105, 106, 107, 106, 105, 105, 104, 104, 103, 102, 102, 101, 100, 102}; Weight june = new Weight( values ); int avg = june.average(); System.out.println("average = " + avg ); } }
To check your method, initialize the array to ten values that have an easily computed average.
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Now add another method that computes the average for a range of days. The method header looks like this:
public int subAverage( int start, int end )
Make the range inclusive,
that is, add up all days from
start
to and
including end
.
You will probably get this wrong.
Check your results, then debug your
method.
In the main()
method,
use this method to compute the average
of the first half of the month and then
the second half of the month.
Print out both averages and the difference
between them.
If the month has an odd number of days
include the middle day in both averages.
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