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Thread: Population class

  1. #1

    Default Population class

    I have made a class that gets the starting population, the percent increase daily and the number of days the organisms will be multiplied.
    public class popul
    	//Creakte private fields
    	private double pop_organism;
    	private int percentIncrease;
    	private int days_multiply;
    	private double new_population=0;
    	//Make a contructor
    	public popul()
    	//take in a argument
    	public void get_popPercent_daysMult(double population,int percent,int days_mult)
    	public void calculate_increase()
    		for(int counter=1;counter<=days_multiply;counter++)
    			System.out.print("Day"+ " "+counter+ " : "+pop_organism);

    My problem seems to lie in the public void calculate_increase method. For some aparents reason I'm getting
    day 1 : 4.0 day 2: 4.0 day 3: 4.0 day 4: 4.0 day 5: 4.0
    I have been working on this for one hour but just can't seem to figure it out! Thanks guys in advance oh and my sample input I'm using is


  2. #2
    Join Date
    Oct 2013
    Manila, Philippines
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    Default Re: Population class

    you have private int percentIncrease (Instance variable)
    and you also have this parameter in get_popPercent_daysMult
    the problem is: it is in Integer. It should be double since your dealing
    with a number that might consist of decimal values.

    you can divide the percent by 100.0 instead of 100
    that will make your result auto cast to double data type.
    Last edited by dicdic; March 11th, 2014 at 11:33 PM.

  3. The Following User Says Thank You to dicdic For This Useful Post:

    GregBrannon (March 12th, 2014)

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