How to round off a float value so that it should not contain 0 after decimal

问题

How to round off a float value if the value is like:

eg:

• 1.0 ==> then it should return 1
• 2.0 ==> then it should return 2

but if the value is like:

• 1.2 ==> then it should return 1.2

• 1.90 ==>then it should return 1.9

I have tried to round off it and also tries different solutions but that doesn't worked for me.

回答1:

You can create a helper function like this

 static public void Normalize(String pattern, double value ) {
    DecimalFormat formatter = new DecimalFormat(pattern);
    String normalizedValue = formatter.format(value);
    System.out.println(normalizedValue);
    }

Normalize("0.#####",2.40); // 2.4
Normalize("0.#####",2.0); // 2

This worked for me.

回答2:

What you're talking about here is a display issue. The "0" in the 1.0 shows how accurate the number is, if you are only displaying 1 then the person reading does not know how accurate that value is (compared with 1.1, 1.9 or even 1.0003).

My suggestion would be to convert your answer to a string and check if the last value is "0", and if so remove it for display purposes (or some other formatting solution).

Note: I wouldn't recommend doing this because it changes the meaning of the value.

来源：https://stackoverflow.com/questions/30396740/how-to-round-off-a-float-value-so-that-it-should-not-contain-0-after-decimal