From 25d77e62e07dc30e37459888975584c0715bb7c0 Mon Sep 17 00:00:00 2001
From: niklas <niklas.birk.nb@gmail.com>
Date: Thu, 23 Nov 2023 16:02:33 +0100
Subject: [PATCH] more stuff

---
 uebung_03/exercise_02/exercise_02a.py | 11 ++++++++
 uebung_03/exercise_02/exercise_02b.py | 23 +++++++++++++++++
 uebung_03/exercise_03/exercise_03a.py | 37 +++++++++++++++++++++++++++
 uebung_03/exercise_03/exercise_03b.py | 33 ++++++++++++++++++++++++
 uebung_04/exercise_06/src/main.rs     |  7 ++---
 5 files changed, 108 insertions(+), 3 deletions(-)
 create mode 100644 uebung_03/exercise_02/exercise_02a.py
 create mode 100644 uebung_03/exercise_02/exercise_02b.py
 create mode 100644 uebung_03/exercise_03/exercise_03a.py
 create mode 100644 uebung_03/exercise_03/exercise_03b.py

diff --git a/uebung_03/exercise_02/exercise_02a.py b/uebung_03/exercise_02/exercise_02a.py
new file mode 100644
index 0000000..e81b8cd
--- /dev/null
+++ b/uebung_03/exercise_02/exercise_02a.py
@@ -0,0 +1,11 @@
+from mpi4py import MPI
+
+comm = MPI.COMM_WORLD
+rank = comm.Get_rank()
+
+if rank == 0:
+    data = "Hello, from process 0!"
+    comm.send(data, dest=1)
+elif rank == 1:
+    received_data = comm.recv(source=0)
+    print(f"Process 1 received: {received_data}")
diff --git a/uebung_03/exercise_02/exercise_02b.py b/uebung_03/exercise_02/exercise_02b.py
new file mode 100644
index 0000000..9dc0ec9
--- /dev/null
+++ b/uebung_03/exercise_02/exercise_02b.py
@@ -0,0 +1,23 @@
+from mpi4py import MPI
+
+comm = MPI.COMM_WORLD
+rank = comm.Get_rank()
+size = comm.Get_size()
+
+send_data = f"Hello, from process {rank}!"
+print(f"I am rank {rank}. I send to process {(rank+1)}")
+print(f"I am rank {rank}. I receive from process {(rank-1)}")
+
+if rank == size-1:
+    comm.send(send_data, dest=(0))
+else:
+    comm.send(send_data, dest=(rank + 1))
+
+recv_data = ""
+
+if rank == 0:
+    recv_data= comm.recv(source=(size - 1))
+else:
+    recv_data= comm.recv(source=(rank - 1))
+
+print(f"I am rank {rank}. I have received: {recv_data}")
diff --git a/uebung_03/exercise_03/exercise_03a.py b/uebung_03/exercise_03/exercise_03a.py
new file mode 100644
index 0000000..600a288
--- /dev/null
+++ b/uebung_03/exercise_03/exercise_03a.py
@@ -0,0 +1,37 @@
+from mpi4py import MPI
+import numpy as np
+import math
+
+comm = MPI.COMM_WORLD
+rank = comm.Get_rank()
+size = comm.Get_size()
+
+chunk = 0
+
+if rank == 0:
+    N = 100000
+    x = np.random.uniform(0,1,(N,1))
+
+    chunksize = math.floor(N / size)
+    for i in range(1,size):
+        from_index = 0 + chunksize * i
+        to_index = (chunksize * (i + 1)) - 1
+        chunk = x[from_index:to_index]
+        comm.send(chunk, dest = i)
+else:
+    chunk = comm.recv(source = 0)
+
+chunk_sum = 0.0
+for i in range(len(chunk)):
+    chunk_sum += chunk[i] * chunk[i]
+
+if rank != 0:
+    comm.send(chunk_sum, dest = 0) 
+
+if rank == 0:
+    sum = chunk_sum 
+
+    for i in range(1,size):
+        sum += comm.recv(source = i)
+
+    print(f"The squared euclidian norm of x is {sum[0]:.2f}.")
diff --git a/uebung_03/exercise_03/exercise_03b.py b/uebung_03/exercise_03/exercise_03b.py
new file mode 100644
index 0000000..1079309
--- /dev/null
+++ b/uebung_03/exercise_03/exercise_03b.py
@@ -0,0 +1,33 @@
+from mpi4py import MPI
+import numpy as np
+import math
+
+comm = MPI.COMM_WORLD
+rank = comm.Get_rank()
+size = comm.Get_size()
+
+chunk = 0
+
+if rank == 0:
+    N = 100000
+    x = np.random.uniform(0,1,(N,1))
+
+    chunksize = math.floor(N / size)
+    for i in range(1,size):
+        from_index = 0 + chunksize * i
+        to_index = (chunksize * (i + 1)) - 1
+        chunk = x[from_index:to_index]
+        comm.send(chunk, dest = i)
+else:
+    chunk = comm.recv(source = 0)
+
+chunk_sum = 0.0
+for i in range(len(chunk)):
+    chunk_sum += chunk[i] * chunk[i]
+
+comm.Barrier()
+
+sum = comm.reduce(chunk_sum, op = MPI.SUM, root = 0)
+
+if rank == 0:
+    print(f"The squared euclidian norm of x is {sum[0]:.2f}.")
diff --git a/uebung_04/exercise_06/src/main.rs b/uebung_04/exercise_06/src/main.rs
index bd2a903..47ed6f7 100644
--- a/uebung_04/exercise_06/src/main.rs
+++ b/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);
     }
-}
\ No newline at end of file
+}