Math.ceil() method giving unexpected result

Question

i am writing program to find area of Triangle. but when i enter the sides length as 1,1,1. then area comes out to be 0.0. So to change this i used Math.ceil(area), method to get the answer to greatest integer value. but still answer comes out to be 0.0. Also tell me that even if i don't use Math.ceil() method then also area should have value .97234 but it automatically shows value 0.0. but for other cases it works fine.

import java.util.Scanner;
import java.util.InputMismatchException;
class Triangle1
{       
    static int counter=1;                   // keep track of the triangle no.
    static int validTriangles=0;                            // calculate no. of valid triangles
    static int unvalidTriangles=0;                      //   calculate no. of unvalid triangles 
    String type;                            // stores the type of all triangles
    int sides[]=new int[3];                         // holds the length of sides of triangle
    Scanner obj =new Scanner (System.in);
    double area;                        // holds area 
    int perimeter;                      // holds perimeter
    Triangle1 ()
    {   
        area=0;
        perimeter=0;
    }


    public void inputAndDetermine()
    {
        try
        {
        System.out.println("enter the length of first side of Triangle"+ " "+ counter +":");
        sides[0]=obj.nextInt();
        System.out.println("enter the length of second side of Triangle"+" " + counter + ":");
        sides[1]=obj.nextInt();
        System.out.println("enter the length of third side of Triangle"+" " + counter + ":");
        sides[2]=obj.nextInt();
        if(sides[0]<=0||sides[1]<=0||sides[2]<=0)
        {
            throw new Exception();
        }
        }
        catch(NumberFormatException ex)
        {
            System.err.println("please enter length of side in numeric format , eg: 2");
        }

        catch(InputMismatchException ex)
        {
            System.err.println("please enter length of side in integer values , eg: 2");
        }
        catch(Exception ex)
        {
            System.err.println("Length of side can neither be negative nor zero, please enter value greter than zero");
        }
        if(((sides[0]+sides[1])>sides[2])&&((sides[1]+sides[2])>sides[0])&&((sides[0]+sides[2])>sides[1]))
        {
            type=determineType();

            validTriangles++;
                }
        else
        {   System.out.println("The Input lenghts of the sides doesn't describe a triangle.");
            System.out.println("------------------------------------------------------------------------");
            unvalidTriangles++;
            type="N/A";
        }
            counter++;

    }
    public String determineType()
    {
        if(sides[0]==sides[1]&&sides[1]==sides[2])
        {
            return "Equilateral";   
        }
        else if(sides[0]==sides[1]||sides[1]==sides[2]||sides[0]==sides[2])
        {
            return "Isoceles";
        }   
        else
        {
            return "Scalene";
        }

    }

        public void calculateArea()
        {
            double s=(sides[0]+sides[1]+sides[2])/2;
            area = Math.sqrt(s*(s-sides[0])*(s-sides[1])*(s-sides[2]));
            if (area<1)
            {
                area=Math.ceil(area);
            }
            else
            {
            area =Math.round(area*100d)/100d;
            }   
        }

        public void calculatePerimeter()
        {
            perimeter=sides[0]+sides[1]+sides[2];
        }

        public void displayResult()
        {
            System.out.println("the Triangle perimeter and area are:");
            System.out.println("        "+ perimeter + "units,  "+ area + "square units." + type);
            System.out.println("------------------------------------------------------------------------");
        }
}

the problem is in calculateArea() Method.

The problem can't be in `calculateArea()` -- because you never call it!!! — ajb, Jun 26 '17 at 04:42
This is a fair amount of code, and I suspect most of it isn't relevant to the workings of `Math.ceil`. Please edit the question to contain the shortest program that will reproduce the problem you're having -- which sounds like it could be done in essentially three lines: `double original ... ; double after = Math.ceil(original); System.out.println(after);` — yshavit, Jun 26 '17 at 04:42
If you want decimal precision you must use a float type or cast to a float when calculating — Peter Krasinski, Jun 26 '17 at 04:42
there is another class Triangle Test that i have not posted here. — GURMEET SINGH, Jun 26 '17 at 04:45
Then please post it. Otherwise we can't tell what's going on. We don't know if perhaps some variables are uninitialized when you call `calculateArea` or what. — ajb, Jun 26 '17 at 04:45
Shouldn't `calculateArea()` simply `return area`? Why do you need a field? — OneCricketeer, Jun 26 '17 at 04:46
Wow, so much code for such a local question. Next time, please try to come up with a minimal example: https://stackoverflow.com/help/mcve — Henry, Jun 26 '17 at 04:52
area = Math.sqrt(s*(s-sides[0])*(s-sides[1])*(s-sides[2])); please check this line. Seems it is returning 0 — pramesh, Jun 26 '17 at 04:53
@ScaryWombat thanks for your help. now the problem is solved — GURMEET SINGH, Jun 26 '17 at 04:53

Math.ceil() method giving unexpected result

0 Answers0