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-rw-r--r--src/num_traits.rs4
-rw-r--r--src/sinusoid.rs42
2 files changed, 38 insertions, 8 deletions
diff --git a/src/num_traits.rs b/src/num_traits.rs
index b6a2ac8..a754787 100644
--- a/src/num_traits.rs
+++ b/src/num_traits.rs
@@ -88,7 +88,7 @@ impl_int_pow!(u64);
pub trait Float {
fn recip(self) -> Self;
- fn PI() -> Self;
+ fn pi() -> Self;
}
macro_rules! impl_float {
@@ -97,7 +97,7 @@ macro_rules! impl_float {
fn recip(self) -> Self {
self.recip()
}
- fn PI() -> Self {
+ fn pi() -> Self {
$pi
}
}
diff --git a/src/sinusoid.rs b/src/sinusoid.rs
index 6ee5019..1f60b03 100644
--- a/src/sinusoid.rs
+++ b/src/sinusoid.rs
@@ -1,6 +1,6 @@
-use std;
-use std::ops::{Add, Sub, Mul, Div, Neg};
-use ::num_traits::{Trig, Pow, Float};
+use std::cmp::{PartialOrd};
+use std::ops::{Add, Sub, Mul, Div, Rem};
+use ::num_traits::{Trig, Float};
// generic number type, but realistically it's only useful for
// floats. Maybe also complex<float>
@@ -25,12 +25,28 @@ impl<T> Sinusoid<T> where T: Float + Copy {
self.frequency.recip()
}
}
-impl<T> Sinusoid<T> where T: Float + Add<Output=T> + Mul<Output=T> + From<u8> + Trig + Copy + std::fmt::Display {
+impl<T> Sinusoid<T> where T: Float + Add<Output=T> + Sub<Output=T> + Mul<Output=T> + Div<Output=T> + From<u16> + Trig + Copy + PartialOrd + Rem<Output=T> {
pub fn radial_frequency(&self) -> T {
- (T::from(2))*T::PI()*self.frequency
+ (T::from(2))*T::pi()*self.frequency
}
pub fn sample(&self, t: T) -> T {
- (self.radial_frequency()*t + self.phase).cos() * self.amplitude
+ (self.radial_frequency()*(t%self.period()) + self.phase).cos() * self.amplitude
+ }
+ //inclusive of start, exclusive of end
+ pub fn sample_range(&self, start: T, end: T, sample_rate: T) -> Vec<T> {
+ let sample_resolution = T::from(1) / sample_rate;
+ let mut result = Vec::new();
+ let mut i: u16 = 0;
+ loop {
+ let t = start + T::from(i)/sample_rate;
+ if t >= end {
+ break;
+ }
+ result.push(self.sample(t));
+ i += 1;
+ }
+
+ result
}
}
@@ -60,4 +76,18 @@ mod tests {
assert!((sinusoid.sample(0.75)+1.0) < f32::EPSILON);
assert!((sinusoid.sample(1.0)-0.0) < f32::EPSILON);
}
+
+ #[test]
+ fn sample_range() {
+ let sinusoid = Sinusoid::new(1.0 as f32, 1.0, -f32::consts::PI/2.0); //AKA sin
+ let samples = sinusoid.sample_range(0.0, 100.0, 4.0);
+ println!("Epsilon is {}", f32::EPSILON);
+ assert_eq!(samples.len(), 400);
+ for i in (0..100).map(|i| i*4) {
+ assert!((samples[i+0]-0.0) < f32::EPSILON, "Sample {} was {}", i+0, samples[i+0]);
+ assert!((samples[i+1]-1.0) < f32::EPSILON, "Sample {} was {}", i+1, samples[i+1]);
+ assert!((samples[i+2]-0.0) < f32::EPSILON, "Sample {} was {}", i+2, samples[i+2]);
+ assert!((samples[i+3]+1.0) < f32::EPSILON, "Sample {} was {}", i+3, samples[i+3]);
+ }
+ }
}