Introduction to IMSL and
VNI
Welcome to OIT’s seminar on IMSL Numerical
Libraries
Sam Gordji, ccsam@olemiss.edu
Weir 107
List of VNI Packages
IMSL
 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
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sweetgum is a Unix
server housed in the
data center building
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sweetgum is primarily
used by researchers
that have large
number crunching
programs
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Limited knowledge of
Unix system is needed
to run Fortran and
IMSL
Accessing Fortran on sweetgum
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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
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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
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“pwd” to print working directory
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“ls” to list files in working directory
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To view a program, enter
“cat file-name.f”
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To launch a Fortran program, enter
“f90 file-name.f”
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To attend a Unix seminar, please contact
assist@mcsr.olemiss.edu
Running IMSL on a PC
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IMSL PC version is available for C
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Users need to have their own copy of C
Topics of the Day
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Creating a simple Fortran Program
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Running a few Fortran Program w/ and w/o
IMSL (nonlin.f, mcsr.f, and test.f)
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Looking at some aspects of Fortran & IMSL
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Download Fortran programs from sweetgum:
/usr/local/appl/examples
Importing a Fortran Program into
sweetgum
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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
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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
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To create an executable on sweetgum enter
f90 $F90FLAGS –o mcsr mcsr.f $LINK_F90
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To run a script called “mcsr", simply enter
mcsr
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Please note that the executable in this case is
called “mcsr"
Output of mcsr.f
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The solution for the 3 by 3 system of
equations is:
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X
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1
2
3
1.000 1.500 1.000
General Information
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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 , or
mathadm@olemiss.edu
General Information
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Email contact
– assist@mcsr.olemiss.edu
To download this and other materials visit:
http://www.mcsr.olemiss.edu/educationsubpage.php?pagename=febcamp09.inc
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Please fill out the performance report and
leave your email address so we may contact
you for follow up questions