Parallel Computing on Windows

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There are many ways to use MPI. In this post I show how to install and use the DeinoMPI implementation which looks very cool and is free.
The screen captures in this post were taken using the nice SnapIt tool.

Part 1: Installing DeinoMPI

After downloading and starting the msi file:








Part 2: Configuring DeinoMPI
2.1 Start the deinoMPI daemon:


2.2 Credentials


Part 3: Testing
In this part I show how to compile a MPI program with the free Bloodshed DevC++ IDE.
I use the famous cpi.c code


This installation is "Local Only" (perhaps in one of my future posts I will show how to use this tool with more than one node):


The Windows Firewall is noticing the new player:


Here is the execution and output window:


It is nice to see the Task Manager showing the 10 parallel running processes:


Part 4: A little-bit Mathematics

The integration in cpi.c is done for f(x)=1/(1+x**2) between 0 to 1.
It is nice to replace this function by f(x)=sqrt(1-x**2) also between 0 to 1 (the unit circle).
Strangely enough, integration of either of these functions between 0 to 1 is equal to Pi/4.
The Sage Symbolic Mathematics tool is a good way to show the difference between the two functions:

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