Calculates the error function (Gauss error function).
Syntax:
ERF(number1, number2)
if number2 is omitted, returns the error function calculated between 0 and number1, otherwise returns the error function calculated between number1 and number2. The error function, also known as the Gauss error function, is defined for ERF(x) as:
Example:
ERF(0.5)
returns 0.520499877813.
ERF(0.2; 0.5)
returns 0.297797288603.