Merge pull request #21 from bandprotocol/update-median

update median

Author: warittornc

packages/kit/Cargo.toml

@@ -6,7 +6,7 @@ license = "Apache-2.0"
 name = "owasm-kit"
 readme = "README.md"
 repository = "https://github.com/bandprotocol/owasm/tree/master/packages/kit"
-version = "0.2.2"
+version = "0.2.3"
 
 [dependencies]
-num = "0.2.1"
+num = "0.4.0"

packages/kit/src/ext/mod.rs

@@ -1,5 +1,6 @@
 //! # Owasm Standard Library
 use crate::oei;
+
 pub mod cmp;
 pub mod stats;
 
@@ -27,11 +28,19 @@ where
 }
 
 /// Returns the median value of the given external ID, ignoring unsuccessful reports.
-pub fn load_median<T>(eid: i64) -> Option<T>
+pub fn load_median_integer<T>(eid: i64) -> Option<T>
+where
+    T: std::str::FromStr + std::cmp::Ord + num::Num + num::NumCast,
+{
+    stats::median_integer(load_input(eid).collect())
+}
+
+/// Returns the median value of the given external ID, ignoring unsuccessful reports.
+pub fn load_median_float<T>(eid: i64) -> Option<T>
 where
-    T: std::str::FromStr + std::cmp::Ord + num::Num,
+    T: std::str::FromStr + num::Float + num::NumCast,
 {
-    stats::median(load_input(eid).collect())
+    stats::median_float(load_input(eid).collect())
 }
 
 /// Returns the majority value of the given external ID, ignoring unsuccessful reports.

packages/kit/src/ext/stats.rs

@@ -1,5 +1,8 @@
 use core::cmp::{Ord, Ordering, PartialEq};
-use num::Num;
+
+use num::{Float, Num, NumCast};
+
+use crate::ext::cmp;
 
 /// Returns the average value of the given data set, or None if data is empty.
 pub fn average<T>(data: Vec<T>) -> Option<T>
@@ -22,31 +25,40 @@ where
 /// Returns the median value using the given compare function, or None if data is empty.
 pub fn median_by<T, F>(mut data: Vec<T>, compare: F) -> Option<T>
 where
-    T: Num,
+    T: Num + NumCast,
     F: FnMut(&T, &T) -> Ordering,
 {
     if data.is_empty() {
         return None;
     }
+
     data.sort_by(compare);
     let mid = data.len() / 2;
     if data.len() % 2 == 0 {
         let rhs = data.swap_remove(mid);
         let lhs = data.swap_remove(mid - 1);
-        Some((lhs + rhs) / (T::one() + T::one()))
+        Some((lhs + rhs) / NumCast::from(2).unwrap())
     } else {
         Some(data.swap_remove(mid))
     }
 }
 
 /// Returns the median value of the given data set, or None if data is empty.
-pub fn median<T>(data: Vec<T>) -> Option<T>
+pub fn median_integer<T>(data: Vec<T>) -> Option<T>
 where
-    T: Ord + Num,
+    T: Ord + Num + NumCast,
 {
     median_by(data, T::cmp)
 }
 
+/// Returns the median value of the given data set, or None if data is empty.
+pub fn median_float<T>(data: Vec<T>) -> Option<T>
+where
+    T: Float + NumCast,
+{
+    median_by(data, cmp::fcmp)
+}
+
 /// Returns the majority value of the given data set, or None if there is no majority.
 pub fn majority<T>(mut data: Vec<T>) -> Option<T>
 where
@@ -87,7 +99,6 @@ where
 #[cfg(test)]
 mod tests {
     use super::*;
-    use crate::ext::cmp;
 
     #[test]
     fn test_average_empty() {
@@ -122,51 +133,51 @@ mod tests {
     #[test]
     fn test_median_odd_int() {
         let vals = vec![3, 2, 5, 7, 2, 9, 1];
-        assert_eq!(median(vals), Some(3));
+        assert_eq!(median_integer(vals), Some(3));
     }
 
     #[test]
     fn test_median_single_int() {
         let vals = vec![3];
-        assert_eq!(median(vals), Some(3));
+        assert_eq!(median_integer(vals), Some(3));
     }
 
     #[test]
     fn test_median_empty() {
         let vals: Vec<i64> = vec![];
-        assert_eq!(median(vals), None);
+        assert_eq!(median_integer(vals), None);
     }
 
     #[test]
     fn test_median_even_int() {
         let vals = vec![3, 2, 5, 7, 2, 10, 32, 1];
-        assert_eq!(median(vals), Some(4));
+        assert_eq!(median_integer(vals), Some(4));
         let vals = vec![13, 36, 33, 45];
-        assert_eq!(median(vals), Some(34));
+        assert_eq!(median_integer(vals), Some(34));
         let vals = vec![13, 15];
-        assert_eq!(median(vals), Some(14));
+        assert_eq!(median_integer(vals), Some(14));
     }
 
     #[test]
     fn test_median_odd_float() {
         let vals = vec![3.5, 2.7, 5.1, 7.4, 2.0, 9.1, 1.9];
-        assert_eq!(median_by(vals, cmp::fcmp), Some(3.5));
+        assert_eq!(median_float(vals), Some(3.5));
     }
 
     #[test]
     fn test_median_single_float() {
         let vals = vec![3.0];
-        assert_eq!(median_by(vals, cmp::fcmp), Some(3.0));
+        assert_eq!(median_float(vals), Some(3.0));
     }
 
     #[test]
     fn test_median_even_float() {
         let vals = vec![3.4, 2.0, 5.7, 7.1, 2.2, 10.1, 32.0, 1.8];
-        assert_eq!(median_by(vals, cmp::fcmp), Some(4.55));
+        assert_eq!(median_float(vals), Some(4.55));
         let vals = vec![13.0, 36.0, 45.0, 33.0];
-        assert_eq!(median_by(vals, cmp::fcmp), Some(34.5));
+        assert_eq!(median_float(vals), Some(34.5));
         let vals = vec![13.0, 36.2];
-        assert_eq!(median_by(vals, cmp::fcmp), Some(24.6));
+        assert_eq!(median_float(vals), Some(24.6));
     }
 
     #[test]