How to round up a value in Java?

Question

I want to round up the value. For example,

23.0f / 10.0f = 2.3f -> round up to 3
11.0f / 10.0f = 1.1f -> round up to 2
15.0f / 10.0f = 1.5f -> round up to 2
67.0f / 10.0f = 6.7f -> round up to 7
1738.0f / 10.0 = 173.8f -> round up to 174

My current approach does not work, it rounds to the nearest integer instead of up:

public class Test {

    private static final DecimalFormat df = new DecimalFormat("0.00");

    public static void main(String[] args) {
        final float a = 23;
        final float b = 10;
        final float k = a / b;
        System.out.println(k);
        final float roundup = Math.round(k * 100) / 100;
        System.out.println(roundOff);
    }
}

How can I achieve the desired behavior in Java?

Your examples do not match your description. "if the decimal point is above 1" should mean that 1.1 rounds to 1, because the decimal (1) is not above 1. Do you perhaps mean you'd like to round **up** if the decimal is above **zero**? — Ryan M, May 08 '22 at 00:35

Dropout · Accepted Answer · 2022-05-08T00:32:00.950

2

Use the Math library, do not reinvent the wheel.

private int roundUp(float value){
    return (int) Math.ceil(value);
}

edited May 08 '22 at 00:32

answered May 08 '22 at 00:26

Dropout

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I would recommend to either the value to `int`. – Turing85 May 08 '22 at 00:28
1

Mark the question as duplicate. Do not reinvent the wheel. – Robby Cornelissen May 08 '22 at 00:29
neither valueOf nor parseInt accept double which is returned from math.ceil – Iłya Bursov May 08 '22 at 00:30
1

@RobbyCornelissen it's not a duplicate of the linked post. The linked post is concerned with integer arithmetics. – Turing85 May 08 '22 at 00:31
@IłyaBursov cast works – Dropout May 08 '22 at 00:32
@Turing85 The answers to the duplicate question more than adequately address the current question. – Robby Cornelissen May 08 '22 at 00:35

How to round up a value in Java?

1 Answers1