How to do it...

1. Open the console and create the folder chapter03/recipe03.
2. Navigate to the directory.
3. Create the round.go file with the following content:

        package main

        import (
          "fmt"
          "math"
        )

        var valA float64 = 3.55554444

        func main() {

          // Bad assumption on rounding
          // the number by casting it to
          // integer.
          intVal := int(valA)
          fmt.Printf("Bad rounding by casting to int: %v\n", intVal)

          fRound := Round(valA)
          fmt.Printf("Rounding by custom function: %v\n", fRound)

        }

        // Round returns the nearest integer.
        func Round(x float64) float64 {
          t := math.Trunc(x)
          if math.Abs(x-t) >= 0.5 {
            return t + math.Copysign(1, x)
          }
          return t
        }

1. Execute the code by running go run round.go in the Terminal.
2. You will see the following output: