sample-code/sqrt.cl

@@ -2,30 +2,27 @@
 //! Square root approximation, and example applications
 
 /// A really small nonzero number
-const EPSILON: f64 // = 8.854... * 10^-12
+const EPSILON: f64 = 8.8541878188 / 1000000000000.0;
-    = 88541878188 as f64
-    / 10000000000 as f64
-    / 1000000000000 as f64;
 
 /// Calcuates the absolute value of a number
 fn f64_abs(n: f64) -> f64 {
     let n = n as f64
-    if n < (0 as f64) { -n } else { n }
+    if n < (0.0) { -n } else { n }
 }
 
 /// Square root approximation using Newton's method
 fn sqrt(n: f64) -> f64 {
     let n = n as f64
-    if n < 0 as f64 {
+    if n < 0.0 {
-        return 0 as f64 / 0 as f64 // TODO: NaN constant
+        return 0.0 / 0.0 // TODO: NaN constant
     }
-    if n == 0 as f64 {
+    if n == 0.0 {
-        return 0 as f64
+        return 0.0
     }
 
     let z = n
     loop {
-        let adj = (z * z - n) / (2 as f64 * z)
+        let adj = (z * z - n) / (2.0 * z)
         z -= adj
         if adj.f64_abs() < EPSILON {
             break z;
@@ -42,18 +39,18 @@ fn pythag(a: f64, b: f64) -> f64 {
 fn quadratic(a: f64, b: f64, c: f64) -> (f64, f64) {
     let a = a as f64; let b = b as f64; let c = c as f64;
     (
-        (-b + sqrt(b * b - 4 as f64 * a * c)) / 2 as f64 * a,
+        (-b + sqrt(b * b - 4.0 * a * c)) / 2.0 * a,
-        (-b - sqrt(b * b - 4 as f64 * a * c)) / 2 as f64 * a,
+        (-b - sqrt(b * b - 4.0 * a * c)) / 2.0 * a,
     )
 }
 
 fn main() {
     for i in 0..10 {
-        println("sqrt(",i,") ≅ ",sqrt(i))
+        println("sqrt(",i,") ≅ ",sqrt(i as f64))
     }
     println("\nPythagorean Theorem")
-    println("Hypotenuse of ⊿(5, 12): ", pythag(5, 12))
+    println("Hypotenuse of ⊿(5, 12): ", pythag(5.0, 12.0))
 
     println("\nQuadratic formula")
-    println("Roots of 10x² + 4x - 1: ", quadratic(10, 44, -1))
+    println("Roots of 10x² + 4x - 1: ", quadratic(10.0, 44.0, -1.0))
 }