I’m working with The Book and doing the exercises on HashMaps.
These are the errors I’m getting, which are are throwing me off because I know the vector can use the .iter() method.
error[E0277]: `&std::slice::Iter<'_, {float}>` is not an iterator
> src\main.rs:29:49

29  let v_modes: HashMap<_, _> = &v_keys.iter().zip(&v.iter()).collect();
 ^^^ `&std::slice::Iter<'_, {float}>` is not an iterator

= help: the trait `std::iter::Iterator` is not implemented for `&std::slice::Iter<'_, {float}>`
= note: required because of the requirements on the impl of `std::iter::IntoIterator` for `&std::slice::Iter<'_, {float}>`
error[E0599]: no method named `collect` found for type `std::iter::Zip<std::slice::Iter<'_, {integer}>, &std::slice::Iter<'_, {float}>>` in the current scope
> src\main.rs:29:64

29  let v_modes: HashMap<_, _> = &v_keys.iter().zip(&v.iter()).collect();
 ^^^^^^^

= note: the method `collect` exists but the following trait bounds were not satisfied:
`std::iter::Zip<std::slice::Iter<'_, {integer}>, &std::slice::Iter<'_, {float}>> : std::iter::Iterator`
`&mut std::iter::Zip<std::slice::Iter<'_, {integer}>, &std::slice::Iter<'_, {float}>> : std::iter::Iterator`
Here is the code I’m writing, trying to finish up the last part of the exercise. The problem is in the let v_modes section.
/*
Given a list of integers, use a vector and return the mean (the average value),
median (when sorted, the value in the middle position), and mode
(the value that occurs most often; a hash map will be helpful here) of the list.
*/
fn main() {
use std::collections::HashMap;
let mut v = vec![32.0, 45.0, 23.0, 65.0, 12.0, 87.0, 99.0, 33.0, 78.0];
let mut v_keys = Vec::new();
{
let mut a = 0;
for i in &v {
a += 1;
v_keys.push(a  1);
}
}
dbg!(&v_keys);
let v_sorted = &v.sort_by(a, b a.partial_cmp(b).unwrap());
let v_len = v.len() as f64;
let v_mid: usize = v.len() as usize / 2;
let v_sorted = &v.sort_by(a, b a.partial_cmp(b).unwrap());
let v_len = v.len() as f64;
let v_mid: usize = v.len() as usize / 2;
let v_modes: HashMap<_, _> = &v_keys.iter().zip(&v.iter()).collect();
let v_median = &v[v_mid as usize];
let mut sum = 0.0;
for i in &v {
println!("{}", i);
}
for i in &v {
sum += i;
println!("{}", &sum);
}
let mean = &sum / &v_len;
dbg!(&v_mid);
dbg!(&v.len());
dbg!(&v_len);
println!("resorted v as {:?}", v_sorted);
println!("v has {:.1} items", &v_len);
println!("all the items in v = {:.1}", &sum);
println!("mean value of all items in v is {:.1}", mean);
println!(
"median of v values is {:.1}, it is number {} in the index",
v_median, v_mid
);
}