Basic Java Program Help (Target-Heart-Rate Calculator)

RoRo979 wrote: »

i dont think that would be the solution as i need the division anwer to be a double. e.g for the 85% part and im 16, it would divide 204 by 100, giving me 2.04, i need to then multiply this 2.04 by 85 which i would get 173.4. but the when i use the return on it it doesnt allow me, if the division became an int it would become 2 by 85 giving me 170

RoRo979 wrote: »

Sorry to intrude on this thread but I don't know where else to ask for help

Could someone please help me with the problem below. I have all the code working except the target heart rate as it cannot return a double for me. It is rounding it thus:

E.g. I'm 16, maximum HR is 204, it should go: 204/100 * 50, but where 204/100 = 2 not 2.04.

Full instructions of the problem I'm working on:

Target-Heart-Rate Calculator

While exercising, you can use a heart-rate monitor to see that your heart rate stays within a safe range suggested by your trainers and doctors. According to the American Heart Association (AHA) , the formula for calculating your maximum heart rate in beats per minute is 220 minus your age in years.

Your target heart rate is a range that’s 50–85% of your maximum heart rate. [Note: These formulas are estimates provided by the AHA. Maximum and target heart rates may vary based on the health, fitness and gender of the individual. Always consult a physician or qualified health care professional before beginning or modifying an exercise program.]

Create a class called HeartRates:

Attributes

The class attributes should include the person's:

• first name
• last name
• date of birth (consisting of separate attributes for the month, day and year of birth).

Methods

• Your class should have a constructor that receives this data as parameters.
• For each attribute provide set and get methods.

The class also should include:

• a method that calculates and returns the person’s age (in years)
• a method that calculates and returns the person’s maximum heart rate
• a method that calculates and returns the person’s target heart rate.

Write a Java application that prompts for the person’s information, instantiates an object of class HeartRates and prints the information from that object— including the person’s first name, last name and date of birth — then calculates and prints the person’s age in (years), maximum heart rate and target-heart-rate range.

The code I have so far:

import java.util.Scanner;
public class test {
    Scanner ronan = new Scanner(System.in);
    private int day;
    private int month;
    private int year;
    private String first;
    private String last;
    private int maximum;
    private int number;
    private int higher;
    private int lower;
    private int total;
    private int age;
    
    public test(String first, String last, int day, int month, int year){
        this.day = day;
        this.month = month;
        this.year= year;
        this.first=first;
        this.last=last;
    }
    public void setDate(int day, int month, int year){
        this.day = day;
        this.month = month;
        this.year= year;    
    }
    public String getName(){
        return first;
    }
    public String getName2(){
        return last;
    }
    public int getDate(){
        return day;
    }
    public int getMonth(){
        return month;
    }
    public int getYear(){
        return year;
    }
    public int age(){
        age = 2013-year;
        return age;    
    }
    public int Maximum(){
        number = 2013 - year;
        total= 220 - number;
        this.total= total;
        return total;
    }
    public int HRH(){
        total=220-age;
        higher = total/100*50;
        return higher;
    }
    public int HRL(){
        total=220-age;
        lower = total/100*85;
        return lower;
    }

}

RoRo979 wrote: »

public class testmain {

    public static void main(String[] args) {
        Scanner imput= new Scanner(System.in);
        test ro = new test("name1", "name2", 28, 8, 1997);
        System.out.printf("Name:%s %s\nDOB: %d/%d/%d\n age:%d\n", ro.getName(), ro.getName2(),ro.getDate(), ro.getMonth(),ro.getYear(), ro.age());
        System.out.printf("your maximum HR is %d\n", ro.Maximum());
        System.out.printf("ideal HR is %d-%d", ro.HRH(),ro.HRL());
    }

}

apologies should of done that at the start

Name:name1 name2
DOB: 28/8/1997
age:16
your maximum HR is 204
ideal HR is 100-170

RoRo979 wrote: »

hi Username99 thanks that was very helpful, just one question, for the target heart rate i am still receiving errors, here is the code i entered

System.out.printf("\nYour target heart rate is %f - %f\n",[B]targetHeartRateMin()[/B], [B]targetHeartRateMin()[/B]);

I also tried doing

System.out.printf("\nYour target is %d- %d\n",[B]targetHeartRateMin()[/B], [B]targetHeartRateMin()[/B]);

but neither seemed to work, how would you go about gettin this, thank you

RoRo979 wrote: »

the return value is coming up null- null?