Question

USING JAVA

Write a program for calculating body fat and body fat percentage. The following simple formulas will be used for our calculations

Body fat formula for female:

A1 = (weight * .732) + 8.987

A2 = wrist measurement / 3.14

A3 = waist measurement * .157

A4 = hip measurement * .249

A5 = forearm measurement * .434

B = A1 + A2 - A3 – A4 + A5

Body fat = weight – B

Body fat percentage = Body fat * 100 / weight

Body fat formula for male:

A1 = (weight * 1.082) + 94.42

A2 = waist measurement * 4.15

B = A1 – A2

Body fat = weight – B

Body fat percentage = Body fat * 100 / weight

Your program should:

a. Ask for the gender and pertinent information for the given gender and calculate and display all the calculated values (A1, A2, etc.). For example, if the gender is Male, you don’t need the wrist measurement.

b. If a gender other than Male or Female is entered, issue an error message and do not calculate/display any data.

c. If the input weight is a negative number or is higher than 400, issue an error message and do not calculate/display any data.

d. Display the following information based on the calculated body fat percentage:

Less than 0 or higher than 400 = An error situation

0 or more, but less than 20   = OK

20 or more, but less than 50 = FINE

50 or more, but 400 or less = NOTHING we can do!

Answer 1

/*
* java program that prompts user to enter the male or female.
* Then weight, wrist, waise, hip and fore arm values from keybaord.
* Then display the results
* */
//BodyFat.java
import java.util.Scanner;
public class BodyFat
{
   public static void main(String[] args)
   {
       //create a Scanner class object
       Scanner console=new Scanner(System.in);
       String gender;
       double weight ;
       double wrist_measurement;
       double waist_measurement;
       double hip_measurement;
       double forearm_measurement;
       double B;
       double A1,A2,A3,A4,A5;
       double bodyfat;
       double fatpercent;

       System.out.printf("Enter male or female: ");
       gender=console.nextLine();
       //check if gender is not either male or female exit the program
       if(!gender.equals("male") && !gender.equals("female"))
       {
           System.out.println("Invalid");
           System.exit(0);
       }
       else
       {
           System.out.printf("Enter weight(kgs): ");
           weight=Double.parseDouble(console.nextLine());
          
           //exit the program if weight above 400
           if(weight<0 || weight>400)
           {
               System.out.println("Invalid");
               System.exit(0);
           }

           System.out.printf("Enter wrist_measurement: ");
           wrist_measurement=Double.parseDouble(console.nextLine());
           System.out.printf("Enter waist_measurement: ");
           waist_measurement=Double.parseDouble(console.nextLine());
           System.out.printf("Enter hip_measurement: ");
           hip_measurement=Double.parseDouble(console.nextLine());
           System.out.printf("Enter forearm_measurement: ");
           forearm_measurement=Double.parseDouble(console.nextLine());
           //check if gender is female
           if(gender.equals("female"))
           {
               A1=(weight*0.732)+8.987;
               A2 = wrist_measurement / 3.14;
               A3 = waist_measurement* .157;
               A4 = hip_measurement * .249;
               A5 =forearm_measurement * .434;
               B = A1 + A2 -A3-A4 + A5;
               bodyfat = weight-B;
               fatpercent = bodyfat * 100 / weight;
           }
           else//check if gender is male
           {
               A1 = (weight * 1.082) + 94.42;
               A2 = waist_measurement * 4.15;
               B = A1-A2;
               bodyfat= weight-B;
               fatpercent = bodyfat* 100.0/ weight;
           }
           //check if fatpercent
           if(fatpercent>400)
               System.out.println(" An error situation");
           else if(fatpercent>=0 && fatpercent<20)
               System.out.println("OK");
           else if(fatpercent>=20 && fatpercent<50)
               System.out.println("FINE");
           else if(fatpercent>=50 && fatpercent<400)
               System.out.println("NOTHING we can do!");
          
          
       }
   }
} //end of the class

Sample Output: