Why does it keep rounding when I use BigDecimal

Question

So I am trying to calculate my average goals blocked by dividing how many I stopped by how many shots have been taken. How can I stop it from rounding my average

counter = goals blocked goalCounter = goals scored

avg.setOnClickListener(new View.OnClickListener() {

    @Override
    public void onClick(View v) {
        // TODO Auto-generated method stub
        BigDecimal avgCalc = new BigDecimal(counter/goalCounter);
        tvDisplayAvg.setText("Goal Avg: " + avgCalc);
    }
});

So I got it to divide and get decimals but is there a way to set a limit of only dividing to the thousandths place?

what type is counter and goalcounter? – Dima Feb 08 '14 at 21:01 — Dima, Feb 08 '14 at 21:01

score 5 · Answer 1 · answered Feb 08 '14 at 21:04

your rounding comes probably from counter/goalCounter if you are using big decimal, stay with it.

avg.setOnClickListener(new View.OnClickListener() {

    @Override
    public void onClick(View v) {

        BigDecimal c = new BigDecimal(counter);
        BigDecimal g = new BigDecimal(goalCounter);
        BigDecimal answer=c.divide(g);

        tvDisplayAvg.setText("Goal Avg: " + amswer.toString());
    }
});

score -1 · Answer 2 · answered Feb 08 '14 at 21:02

-1

The problem might be that counter and goalCounter are both ints. Try casting one of them to double when you divide (e.g. counter/(double)goalCounter). This is because if Java sees you dividing two integers, the result will also be an integer.

If they are not ints (i.e. they are floats or doubles), the float and double types have limited precision, and the BigDecimal class was created to rectify this situation. Make two BigDecimals - one for each variable - and then assign avgCalc to their quotient.

answered Feb 08 '14 at 21:02

Epiglottal Axolotl

1,048
8
17

double is very bad idea if you want big decimal precision – Dima Feb 08 '14 at 21:06
Which is why my answer has two parts. – Epiglottal Axolotl Feb 08 '14 at 21:13

Why does it keep rounding when I use BigDecimal

2 Answers2