Find median of array numbers and return them

fn median(arr: &[f32]) -> f32 {
    let mut length: f32 = arr.len() as f32;
    let mut length_i32: i32 = arr.len() as i32;
    let mut arr_sorted = arr.clone();
    arr_sorted.sort_by(|a, b| a.partial_cmp(b).unwrap());
    if length % 2. == 0. {
        (arr_sorted[length_i32/2] + arr_sorted[(length_i32/2)-1])/2.
    } else {
        arr_sorted[(length_i32/2) as usize]
    }
}