$isnumber

Tests if an expression produces a valid number after its evaluation.

$isnumber(expression)

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.