(string->number string radix)
(string->number string)
Returns a number of the maximally precise representation expressed by the given string. Radix must be an exact integer, either 2, 8, 10, or 16. If supplied, radix is a default radix that may be overridden by an explicit radix prefix in string (e.g. “#o177”). If radix is not supplied, then the default radix is 10. If string is not a syntactically valid notation for a number, then string->number returns #f.
A number is returned.
(string->number "100") => 100
(string->number "100" 16) => 256
(string->number "1e2") => 100.0
(string->number "15##") => 1500.0