Scala and Java BigDecimal

Question

I want to switch from Java to a scripting language for the Math based modules in my app. This is due to the readability, and functional limitations of mathy Java.

For e.g, in Java I have this:

BigDecimal x = new BigDecimal("1.1");
BigDecimal y = new BigDecimal("1.1");
BigDecimal z = x.multiply(y.exp(new BigDecimal("2"));

As you can see, without BigDecimal operator overloading, simple formulas get complicated real quick.

With doubles, this looks fine, but I need the precision.

I was hoping in Scala I could do this:

var x = 1.1;
var y = 0.1;
print(x + y);

And by default I would get decimal-like behaviour, alas Scala doesn't use decimal calculation by default.

Then I do this in Scala:

var x = BigDecimal(1.1);
var y = BigDecimal(0.1);
println(x + y);

And I still get an imprecise result.

Is there something I am not doing right in Scala?

Maybe I should use Groovy to maximise readability (it uses decimals by default)?

Answer 1

I don't know Scala, but in Java new BigDecimal(1.1) initializes the BigDecimal with a double value and thus it is not exactly equal to 1.1. In Java you have to use new BigDecimal("1.1") instead. Maybe that will help in Scala as well.