Java, rounding a double to two decimal places -

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i'm trying round double nearest 2 decimal places however, rounding nearest full number.

for example, 19634.0 instead of 19634.95.

this current code use rounding

double area = math.round(math.pi*radius()*radius()*100)/100;

i can't see going wrong.

many help.

well, math.round(math.pi*radius()*radius()*100) long. 100 int.

so math.round(math.pi*radius()*radius()*100) / 100 become long (19634).

change math.round(math.pi*radius()*radius()*100) / 100.0. 100.0 double, , result double (19634.95).


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