Solved first question and created python shared virtual venv

.gitignore

+/pyenv/

Q1/Note.txt

+note for diaa don't forget to run this on the cluster when u are in hiast
+
+
+also don't forget to pass the host file as argument
+
+mpirun -np 3 --hostfile mpi_hosts python .py
+

Q1/mpi_hosts

+master
+slave1 user=mpiuser
+slave2 user=mpiuser

Q1/mpi_prefix_sum.py

+from mpi4py import MPI
+import numpy as np
+
+def prefix_mpi(local_in, comm):
+    rank = comm.Get_rank()
+    size = comm.Get_size()
+
+    # step 1
+    local_sum = np.sum(local_in)
+
+    
+    block_sums = comm.gather(local_sum, root=0)
+
+    #step 2
+    if rank == 0:
+        block_prefix = np.zeros(size, dtype=int)
+        for i in range(1, size):
+            block_prefix[i] = block_prefix[i - 1] + block_sums[i - 1]
+    else:
+        block_prefix = None
+
+    
+    offset = comm.scatter(block_prefix, root=0)
+
+    #step 3
+    local_out = np.zeros(len(local_in), dtype=int)
+    current = offset
+    for i in range(len(local_in)):
+        local_out[i] = current
+        current += local_in[i]
+
+    return local_out
+
+
+def prefix_sequential(arr):
+    out = np.zeros(len(arr), dtype=int)
+    for i in range(1, len(arr)):
+        out[i] = out[i - 1] + arr[i - 1]
+    return out
+
+
+# start of program
+comm = MPI.COMM_WORLD
+rank = comm.Get_rank()
+size = comm.Get_size()
+
+N = 12  
+local_n = N // size
+
+# 
+if rank == 0:
+    np.random.seed(42)
+    data = np.random.randint(0, 11, size=N)
+    print("Input array:", data)
+else:
+    data = None
+
+local_data = np.zeros(local_n, dtype=int)
+comm.Scatter(data, local_data, root=0)
+
+
+local_result = prefix_mpi(local_data, comm)
+
+
+if rank == 0:
+    result = np.zeros(N, dtype=int)
+else:
+    result = None
+
+comm.Gather(local_result, result, root=0)
+
+
+if rank == 0:
+    seq = prefix_sequential(data)
+    print("Parallel result :", result)
+    print("Sequential result:", seq)
+    print("Correct:", np.array_equal(result, seq))

mpiPythonTest.py

+from mpi4py import MPI
+import socket
+
+comm = MPI.COMM_WORLD
+rank = comm.Get_rank()
+size = comm.Get_size()
+
+print(f"Hello from rank {rank}/{size} on {socket.gethostname()}")