From 4baea29904442f98eef6974490951fcb7cad1320 Mon Sep 17 00:00:00 2001
From: Daniel Boros <dancixx@gmail.com>
Date: Thu, 29 Aug 2024 18:07:18 +0200
Subject: [PATCH] feat: calc scale factor once

---
 src/noises/fgn.rs | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/noises/fgn.rs b/src/noises/fgn.rs
index 2eaf2c8..d816cde 100644
--- a/src/noises/fgn.rs
+++ b/src/noises/fgn.rs
@@ -109,9 +109,10 @@ impl Generator for FgnFft {
     let fft_handler = self.fft_handler.clone();
     let mut fgn_fft = self.fft_fgn.clone();
     ndfft_par(&fgn, &mut fgn_fft, &fft_handler, 0);
+    let scale_factor = self.t.powf(self.hurst) * (self.n as f64).powf(-self.hurst);
     let fgn = fgn_fft
       .slice(s![1..self.n - self.offset + 1])
-      .mapv(|x: Complex<f64>| (x.re * (self.n as f64).powf(-self.hurst)) * self.t.powf(self.hurst));
+      .mapv(|x: Complex<f64>| x.re * scale_factor);
     fgn
   }