more stuff

uebung_04/exercise_06/src/main.rs

@@ -9,7 +9,7 @@ fn main() {
     let size = world.size();
     let rank = world.rank();
 
-    let support_points = 20;
+    let support_points = 100;
     let a = 0.0;
     let b = 1.0;
     let N = (b - a) / size as f64;
@@ -17,6 +17,7 @@ fn main() {
     let f = |x: f64| 1.0 / (1.0 + x.powi(2)) as f64; // function
     let n = (support_points / size) as u32; // fewer ranks should also use an appropriate amount of support points; the support points are distributed among the ranks
     let partial_integral = trapezoidal_rule(f, a + rank as f64 * N, a + (rank + 1) as f64 * N, n);
+    println!("Rank {}: Partial integral is {} on [{},{}]", rank, partial_integral, (a + rank as f64 * N), (a + (rank + 1) as f64 * N));
 
     world.barrier();
 
@@ -26,7 +27,7 @@ fn main() {
 
     if rank == 0 {
         println!("The approximated integral is {}", integral);
-        println!("The error is {}", (integral - (PI / 4.0)).abs());
+        println!("The error is |{:.7} - {:.7}| = {}", (PI / 4.0), integral, (integral - (PI / 4.0)).abs());
     }
 }
 
@@ -72,4 +73,4 @@ mod tests {
 
         assert!((expected - actual).abs() < tolerance, "Integral is {} but should be {}", actual, expected);
     }
-}
+}