Move complex stuff to a separate crate

Cargo.toml

@@ -3,11 +3,14 @@ name = "fft"
 version = "0.0.1"
 authors = ["Ivan Ukhov <ivan.ukhov@gmail.com>"]
 license = "MIT"
-repository = "https://github.com/hilbert-space/fft"
-homepage = "https://github.com/hilbert-space/fft"
+repository = "https://github.com/stainless-steel/fft"
+homepage = "https://github.com/stainless-steel/fft"
 description = """
 The package provides an algorithm to compute the discrete Fourier transform and
 its inverse."""
 
+[dependencies]
+complex = "*"
+
 [dev-dependencies]
 assert = "*"

src/complex.rs

@@ -1,42 +0,0 @@
-use std::ops::{Add, Mul, Sub};
-
-/// A complex number.
-#[allow(non_camel_case_types)]
-#[derive(Clone, Copy, Debug)]
-pub struct c64(pub f64, pub f64);
-
-impl Add for c64 {
-    type Output = Self;
-
-    #[inline(always)]
-    fn add(self, rhs: c64) -> c64 {
-        c64(self.0 + rhs.0, self.1 + rhs.1)
-    }
-}
-
-impl Mul for c64 {
-    type Output = Self;
-
-    #[inline(always)]
-    fn mul(self, rhs: c64) -> c64 {
-        c64(self.0 * rhs.0 - self.1 * rhs.1, self.0 * rhs.1 + self.1 * rhs.0)
-    }
-}
-
-impl Mul<f64> for c64 {
-    type Output = Self;
-
-    #[inline(always)]
-    fn mul(self, rhs: f64) -> c64 {
-        c64(self.0 * rhs, self.1 * rhs)
-    }
-}
-
-impl Sub for c64 {
-    type Output = Self;
-
-    #[inline(always)]
-    fn sub(self, rhs: c64) -> c64 {
-        c64(self.0 - rhs.0, self.1 - rhs.1)
-    }
-}

src/lib.rs

@@ -1,7 +1,16 @@
-use std::slice;
+//! [Algorithm][1] to compute the [discrete Fourier transform][2] and its
+//! inverse.
+//!
+//! [1]: https://en.wikipedia.org/wiki/Fast_Fourier_transform
+//! [2]: https://en.wikipedia.org/wiki/Discrete_Fourier_transform
+
+// The implementation is based on:
+// http://www.librow.com/articles/article-10
 
-mod complex;
-pub use complex::c64;
+extern crate complex;
+
+use complex::c64;
+use std::slice;
 
 /// A means of obtaining a slice of mutable complex numbers.
 pub trait AsMutComplex<'l> {
@@ -125,15 +134,3 @@ fn scale(data: &mut [c64], n: usize) {
         data[position] = data[position] * factor;
     }
 }
-
-#[cfg(test)]
-mod tests {
-    use c64;
-    use std::mem;
-
-    #[test]
-    fn size_of() {
-        assert_eq!(mem::size_of::<c64>(), 2 * mem::size_of::<f64>());
-        assert_eq!(mem::size_of::<[c64; 42]>(), 2 * mem::size_of::<[f64; 42]>());
-    }
-}