more stuff

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}")

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}")

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}.")

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}.")