I try to write generic method and specify some type T: num_traits::float::Float from num-traits crate. How should I ask &T to implement basic numeric methods such as multiplication?
use splines::{Interpolation, Key, Spline, interpolate};
use num_traits::{float::Float, identities};
use conv::prelude::*;
struct Interpolator<T>
where T: Float + interpolate::One + interpolate::Trigo {
target_x: Vec<T>,
}
impl<T> Interpolator<T>
where T: Float + interpolate::One + interpolate::Trigo {
fn interpolate<U>(&self, x: &[T], y: &[U]) -> Vec<U>
where U: Float + identities::Zero {
assert_eq!(x.len(), y.len());
let key_iter = x.iter().zip(y).map(|(x, y)| Key::new(x, y, Interpolation::Linear));
let spline = Spline::from_iter(key_iter);
let result: Vec<U> = self.target_x.iter().map(|x| spline.sample(x).unwrap_or(identities::zero())).collect();
result
}
}
fn main() {
}
Cargo.toml
[package]
name = "name"
version = "0.1.0"
edition = "2018"
[dependencies]
conv = "0.3.2"
splines = "1.0.0-rc.3"
num-traits = "0.2"
Compilation errors:
error[E0277]: the trait bound `&T: splines::interpolate::One` is not satisfied
--> src/main.rs:18:66
|
18 | let result: Vec<U> = self.target_x.iter().map(|x| spline.sample(x).unwrap_or(identities::zero())).collect();
| ^^^^^^ the trait `splines::interpolate::One` is not implemented for `&T`
error[E0277]: the trait bound `&T: splines::interpolate::Trigo` is not satisfied
--> src/main.rs:18:66
|
18 | let result: Vec<U> = self.target_x.iter().map(|x| spline.sample(x).unwrap_or(identities::zero())).collect();
| ^^^^^^ the trait `splines::interpolate::Trigo` is not implemented for `&T`
error[E0277]: cannot multiply `&T` to `&T`
--> src/main.rs:18:66
|
18 | let result: Vec<U> = self.target_x.iter().map(|x| spline.sample(x).unwrap_or(identities::zero())).collect();
| ^^^^^^ no implementation for `&T * &T`
|
= help: the trait `std::ops::Mul` is not implemented for `&T`
= help: consider adding a `where &T: std::ops::Mul` bound
error[E0277]: cannot divide `&T` by `&T`
--> src/main.rs:18:66
|
18 | let result: Vec<U> = self.target_x.iter().map(|x| spline.sample(x).unwrap_or(identities::zero())).collect();
| ^^^^^^ no implementation for `&T / &T`
|
= help: the trait `std::ops::Div` is not implemented for `&T`
= help: consider adding a `where &T: std::ops::Div` bound
error[E0277]: the trait bound `&U: splines::interpolate::Interpolate<&T>` is not satisfied
--> src/main.rs:18:66
|
18 | let result: Vec<U> = self.target_x.iter().map(|x| spline.sample(x).unwrap_or(identities::zero())).collect();
| ^^^^^^ the trait `splines::interpolate::Interpolate<&T>` is not implemented for `&U`
error[E0277]: cannot add `&T` to `&T`
--> src/main.rs:18:66
|
18 | let result: Vec<U> = self.target_x.iter().map(|x| spline.sample(x).unwrap_or(identities::zero())).collect();
| ^^^^^^ no implementation for `&T + &T`
|
= help: the trait `std::ops::Add` is not implemented for `&T`
= help: consider adding a `where &T: std::ops::Add` bound
= note: required because of the requirements on the impl of `splines::interpolate::Additive` for `&T`
error[E0277]: cannot subtract `&T` from `&T`
--> src/main.rs:18:66
|
18 | let result: Vec<U> = self.target_x.iter().map(|x| spline.sample(x).unwrap_or(identities::zero())).collect();
| ^^^^^^ no implementation for `&T - &T`
|
= help: the trait `std::ops::Sub` is not implemented for `&T`
= help: consider adding a `where &T: std::ops::Sub` bound
= note: required because of the requirements on the impl of `splines::interpolate::Additive` for `&T`
error[E0277]: the trait bound `&U: num_traits::identities::Zero` is not satisfied
--> src/main.rs:18:86
|
18 | let result: Vec<U> = self.target_x.iter().map(|x| spline.sample(x).unwrap_or(identities::zero())).collect();
| ^^^^^^^^^^^^^^^^ the trait `num_traits::identities::Zero` is not implemented for `&U`
|
= note: required by `num_traits::identities::zero`
error[E0277]: a collection of type `std::vec::Vec<U>` cannot be built from an iterator over elements of type `&U`
--> src/main.rs:18:107
|
18 | let result: Vec<U> = self.target_x.iter().map(|x| spline.sample(x).unwrap_or(identities::zero())).collect();
| ^^^^^^^ a collection of type `std::vec::Vec<U>` cannot be built from `std::iter::Iterator<Item=&U>`
|
= help: the trait `std::iter::FromIterator<&U>` is not implemented for `std::vec::Vec<U>`
error: aborting due to 9 previous errors
For more information about this error, try `rustc --explain E0277`.
error: Could not compile `trait_generic`.
