Stefan Tiedje wrote:

atoi as I understand it should convert the symbol "3.14159" into list of integers/floats. "51 46 49 52 51 53 57" as these are the ascii codes for the corresponding letters (including the decimal point).

atoi means "ascii to integer" and should output the ascii code for a given character.

[atoi] works similar to the C standard function atoi(), which converts a string, representing a (integer) number, to that number.

What you describe is something entirely different: breaking up a string into ascii codes. This is done by the [spell] object, if I remember well.