Rounding $variable to three decimals

[blabla_1983]

 Hi,

I'm using a variable to calculate the average of a bunch of Longs. The variable class is java.lang.Long.  It prints out the average correctly except for 1 small issue. 

Some of the numbers are too short (12.9) while others are too long(45.666666666667). I tried to edit the expression of the Text Field so that it would round to three decimals but it only seems to print  no decimals (39 or 45, not 39.xxx or 45.xxx).

All I want to do is round every printed value to three decimal places. If there is no value then it fills it in with a 0.

 

My expression that I tried using is: 

Code:

Math.round((double)(new BigDecimal((double)$V{snr_average}).multiply(1000.0)).divide(1000.0))

[blabla_1983]

Sorry for the post. I figured out how to do it. While it does not place zeros until it fills up the three slots, it does manage to round it.

(Math.round($V{variable_name}*1000.0))/1000.0