How to remove trailing zero in a String value and remove decimal point

Question

How do I remove trailing zeros in a String value and remove decimal point if the string contains only zeros after the decimal point? I'm using the below code:

String string1 = Double.valueOf(a).toString()

This removes trailing zeros in (10.10 and 10.2270), but I do not get my expected result for 1st and 2nd inputs.

Input

Expected output

@ScaryWombat The proposed duplicate has a `double` as the input. This question has a `String`. — jdphenix, Aug 28 '14 at 07:14
@jdphenix so why does OP do `String string1 = Double.valueOf(a).toString()` — Scary Wombat, Aug 28 '14 at 07:22
@ScaryWombat Because I didn't read the question closely enough. Oops. — jdphenix, Aug 28 '14 at 07:23

jdphenix · Answer 1 · 2014-08-28T06:41:42.880

The Java library has a built-in class that can do this for it. It's BigDecimal.

Here is an example usage:

BigDecimal number = new BigDecimal("10.2270");  
System.out.println(number.stripTrailingZeros().toPlainString());

Output:

10.227

Note: It is important to use the BigDecimal constructor that takes a String. You probably don't want the one that takes a double.

Here's a method that will take a Collection<String> and return another Collection<String> of numbers with trailing zeros removed, gift wrapped.

public static Collection<String> stripZeros(Collection<String> numbers) {
    if (numbers == null) { 
        throw new NullPointerException("numbers is null");
    }

    ArrayList<String> value = new ArrayList<>(); 

    for (String number : numbers) { 
        value.add(new BigDecimal(number).stripTrailingZeros().toPlainString());
    }

    return Collections.unmodifiableList(value);
}

Example usage:

ArrayList<String> input = new ArrayList<String>() {{ 
    add("10.0"); add("10.00"); add("10.10"); add("10.2270"); 
}};

Collection<String> output = stripZeros(input);
System.out.println(output);

Outputs:

[10, 10, 10.1, 10.227]

I discovered that `stripTrailingZeros()` with also a call to `toPlainString()` results in output that is outside of your spec. I have corrected my answer. — jdphenix, Aug 28 '14 at 06:42
while technically correct it is not useful for me, case in point: `1.23` becomes `1.229999999999999982236431605997495353221893310546875`. So yes, no trailing zeros for sure – — ycomp, Jan 05 '18 at 03:56

score -1 · Answer 2 · answered Aug 28 '14 at 06:03

-1

Try

DecimalFormat decimalFormat = new DecimalFormat("#.##");
String string1 = decimalFormat.format(10.000);

answered Aug 28 '14 at 06:03

Viraj

5,083
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This would remove anything beyond the 2nd mantissa digit. – jdphenix Aug 28 '14 at 06:50

TheLostMind · Answer 3 · 2014-08-28T06:18:49.783

-4

Try regex like this :

public static void main(String[] args) {
    String s = "10.0";
    System.out.println(s.replaceAll("[0]+$", "").replaceAll("(\\.)(?!.*?[1-9]+)", ""));

}

O/P:
10

input :String s = "10.0750";
O/P : 10.075

input : String s = "10.2750";
O/P : 10.275

edited Aug 28 '14 at 06:18

answered Aug 28 '14 at 06:13

TheLostMind

35,966
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68
104

2

I don't mind getting downvoted. But I would like to know **why**? – TheLostMind Aug 28 '14 at 07:00
not the DV, but as someone else said "May not work in every locale. Some use the decimal point as group separators" – Scary Wombat Aug 29 '14 at 00:01

How to remove trailing zero in a String value and remove decimal point

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