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roc-rs
Rate Of Change (ROC) implementation in rust
use roc_rs::ROC;
use ta_common::traits::Indicator;
let mut roc = ROC::new(1, None);
let res = roc.next(100 as f64);
assert_eq!(None, res);
let res = roc.next(50 as f64);
assert_eq!(Some(-50_f32), res);
Calculation
ROCR=(Current Price/Price Prev n Ago);
ROCP=ROCR-1;
ROC100=(ROCR)*100;
ROC=(ROCR-1)*100; //DEFAULT