datatype("This String","A")
returns a "1" (true) because the string evaluates as Alphanumeric
datatype("This String",":N")
returns a "0" (false) because the string does not evaluate as Numeric
datatype("123.45")
retuns "NUM" because the string is a valid REXX number
DataTest = datatype("This String")
assigns the value "CHAR" to the variable DataTest