I am in need of an absolute value function for floats in OCaml and the core language doesn't seem to possess one, so I wrote the following:
let absF (f:float) = if f > 0.0 then f else (f *. -1.0);;which seems to work for positives but not for negatives, citing:
This expression has type float -> float but is here used with type int
What is the error in my logic?
Best Answer
The core language does have one, abs_float.
Also, you can use ~-. to denote unary negation, and this applies to integers as well with the ~- operator. You can define such an operator (even though it already exists) like this:
let (~-) a : int = 0 - alet (~-.) a : float = 0.0 -. aWhen you type
absF -1.0;;OCaml interprets it as
(absF) - (1.0);;i.e. as a subtraction. Instead, do
absF (-1.0);;if you have int value can use
# abs(-1)- : int = 1else if you have a float
# abs_float(-1.0)- : float = 1.