Added correlation function which updated array in place

1 files changed, 16 insertions, 1 deletions

diff --git a/src/emscripten_api.rs b/src/emscripten_api.rs
index c371d86..0f1bcc7 100644
--- a/src/emscripten_api.rs
+++ b/src/emscripten_api.rs
@@ -2,10 +2,10 @@ use transforms;
 
 use std::os::raw::c_char;
 use std::ffi::CString;
+use std::slice;
 
 #[no_mangle]
 pub extern "C" fn find_fundamental_frequency(signal: *const f32, signal_length: isize, sample_rate: f32) -> f32 {
-    use std::slice;
     let signal_slice = unsafe {
         &slice::from_raw_parts(signal, signal_length as usize)
     };
@@ -25,3 +25,18 @@ pub extern "C" fn hz_to_pitch(hz: f32) -> *mut c_char {
 		.unwrap()
         .into_raw()
 }
+
+#[no_mangle]
+pub extern "C" fn correlation(signal: *mut f32, signal_length: isize) {
+    let signal_slice = unsafe {
+        &slice::from_raw_parts(signal, signal_length as usize)
+    };
+
+    let correlated_signal = transforms::correlation(&signal_slice);
+
+    unsafe {
+        for (i, cor) in correlated_signal.iter().enumerate() {
+            *signal.offset(i as isize) = *cor;
+        }
+    }
+}