Returns a string representation of the BigDecimal rounded to the specified
number of digits after the decimal point.
toFixed(digits, roundingMode)
digits
The number of digits after the decimal point.
roundingMode optional
A string specifying the rounding mode: "floor", "ceiling", "down", "up", "half-even", "half-up". Defaults to "half-up".
A string representing the value.
123.4567m.toFixed(1)
"123.5"
123.4567m.toFixed(1, "down")
"123.4"