Function rate 

pub fn rate(bytes_per_sec: f64) -> String

Format a transfer rate from bytes-per-second with base-1024 IEC units and a /s suffix (512 B/s, 6.4 MiB/s). Negative inputs clamp to zero.

use tilo_ui::format::rate;
assert_eq!(rate(0.0), "0 B/s");
assert_eq!(rate(512.0), "512 B/s");
assert_eq!(rate(6_710_886.0), "6.4 MiB/s");