Introduction to IMSL and VNI

Welcome to OIT’s seminar on IMSL Numerical Libraries

Sam Gordji, ccsam@olemiss.edu

Weir 107

List of VNI PackagesIMSL

IMSL for Fortran is a comprehensive package containing Math, stat., and special functions

IMSL for C++ is a comprehensive package containing Math, stat., and special functions

IMSL is available only on sweetgum

IMSL is a set of subroutines called by a Fortran, Python, or C program

Accessing Fortran on sweetgum sweetgum is a Unix

server housed in the data center building

sweetgum is primarily used by researchers that have large number crunching programs

Limited knowledge of Unix system is needed to run Fortran and IMSL

Accessing Fortran on sweetgum

Fortran and IMSL may be accessed from the network.

Steps to access sweetgum from a Windows PC

– Request a sweetgum account from assist@mcsr.olemiss.edu

– Download/Install SSH Secure Shell Client from http://www.mcsr.olemiss.edu/appssubpage.php?pagename=ssh2.inc

– Click “Secure Shell Client”

Accessing Fortran on sweetgum

sweetgum is ready to execute Fortran jobs

A Few Useful Unix Commands

cat --- for displaying a file cd --- change directory cd 1--- to move to sub-directory 1 & so

on cp --- for copying files rm --- remove a file pico --- a Unix editor

A Few Useful Unix Commands “pwd” to print working directory

“ls” to list files in working directory

To view a program, enter “cat file-name.f”

To launch a Fortran program, enter “f90 file-name.f”

To attend a Unix seminar, please contact assist@mcsr.olemiss.edu

Running IMSL on a PC

IMSL PC version is available for C

Users need to have their own copy of C

Topics of the Day Creating a simple Fortran Program

Running a few Fortran Program w/ and w/o IMSL (nonlin.f, mcsr.f, and test.f)

Looking at some aspects of Fortran & IMSL

Download Fortran programs from sweetgum: /usr/local/appl/examples

Importing a Fortran Program into sweetgum

Download your Fortran program to your desktop

In sweetgum enter “ vi mcsr.f ” Press “ enter ” Enter “ i ” Copy and paste your Fortran program from

your desktop Enter “ : ” Enter “ wq ” and press enter to save your

program which you named “ mcsr.f ”

Text copy of mcsr.f• PARAMETER (IPATH=1, LDA=3, N=3)• REAL A(LDA,LDA), B(N), X(N)• c This is a comment line. Above 2 lines define the parameters needed for matrix

inversion• c Set values for A and B• c• c A = ( 33.0 16.0 72.0)• c (-24.0 -10.0 -57.0)• c ( 18.0 -11.0 7.0)• c Above is the Matrix A and below is the vector B• c B = (129.0 -96.0 8.5)• c• DATA A/33.0, -24.0, 18.0, 16.0, -10.0, -11.0, 72.0, -57.0, 7.0/• DATA B/129.0, -96.0, 8.5/• c Below subroutine LSLRG is called to solve the 3 by 3 equation• CALL LSLRG (N, A, LDA, B, IPATH, X)• c Print results • CALL WRRRN ('X', 1, N, X, 1, 0)• END

Running Fortran on sweetgum To create an executable on sweetgum enter

f90 $F90FLAGS –o mcsr mcsr.f $LINK_F90

To run a script called “mcsr", simply enter

mcsr

Please note that the executable in this case is called “mcsr"

Output of mcsr.f The solution for the 3 by 3 system of

equations is:

X

1 2 3

1.000 1.500 1.000

General Information

IT staff will assist users to access these packages. We also assist users to find the proper procedure to analyze their data. If you need assistance please send an email to Sam Gordji at ccsam@olemiss.edu,assist@mcsr.olemiss.edu , ormathadm@olemiss.edu

General Information

Email contact– assist@mcsr.olemiss.edu

To download this and other materials visit: http://www.mcsr.olemiss.edu/educationsubpage.php?pagename=febcamp09.inc

Please fill out the performance report and leave your email address so we may contact you for follow up questions