Tests if a character string contains a valid number.
$isnumber(string)
| string | a character string or an expression that evaluates to a character string |
1-character binary string. Evaluates to 1 ($True) if string meets the validation test; otherwise, evaluates to 0 ($False).
This function tests if a particular character string is a valid number.
$isnumber(2+3)
Evaluates to $True.
$isnumber($trim(LastName))
Evaluates to $False.