Fill ArrayBuffer with pairs of Double

Question

I need some guidance here, please.

What I have:

import scala.collection.mutable.ArrayBuffer
var buffer = ArrayBuffer.empty[(Double, Double)]

and I want to fill the buffer with pairs. I'm trying this but it doesn't work:

for(someCycle){
    buffer += (someDouble, someOtherDouble)
}

the error:

 error: type mismatch;
 found   : Double
 required: (Double, Double)
              buffer += (someDouble, otherDouble)

I understand the error but I can't figure out the right syntax.

Answer 1

Since += is a function, the compiler is inferring it as:

buffer.+=(someDouble, someOtherDouble)

Making it think you're trying to pass two arguments to += instead of one (the error message is a bit misleading).

You need an additional parenthesis:

buffer += ((someDouble, someOtherDouble))

Or alternatively:

buffer += (someDouble -> someOtherDouble)