This function rounds a to the nearest integer value. The result will have the data type BigDecimal if the param a was a BigDecimal or BigInteger. Otherwise, the result will have the type Double.

If a is not a numerical value, the function returns 0.0, see examples below.

Note: Please use values type-safe. In a commercial context, values should consistently be handled as BigDecimal data types. In a scientific field, the high-precision data type Double is better suited.