DIVIMP User Manual

Version 6.02

J.D. Elder

University of Toronto

Institute for Aerospace Studies






Table of Contents: DIVIMP User Manual



Locations of DIVIMP files

What files are required and what do they do?

The Input files: How to set up a case!

Executing DIVIMP: The various shell scripts

The Output files: Contents and Meaning

Monitoring Execution and Job Management

Appendix A : Shell Scripts






DIVIMP User Manual

The purpose of this manual is to provide information that will enable a reader to compile, execute and to monitor the execution of DIVIMP cases. There are several different possible strategies to allowing multiple users access to the DIVIMP directories. In order to protect the code itself and the shell scripts which run it, it was decided to make individualized copies of the shell scripts for each user. These shell scripts will run the code in the user's home directory. They will also obtain the data files, which control the simulation, from a subdirectory in the user's home directory. However, all results can be stored in the standard DIVIMP results directory, which can be read and written by all users. This will make it possible for all users to erase old results files if the disk space becomes limited while preserving the ability of each user to run their own cases in an independent fashion. It is the responsibility of each user to keep track of the amount of disk space being used by results files and to delete and/or back them up on a regular basis. It is also up to the users to cooperate in scheduling the CPU usage in order to most efficiently utilize the machine resources. Different sites running DIVIMP will have different policies.

This manual describes the general DIVIMP installation in Toronto on an IBM RS6000 workstation which runs a variant of the UNIX operating system known as AIX. It does not apply to installations like that on the IBM3090 at JET (though it may apply to the installation on the JAC cluster at JET), or a typical Cray installation. Other UNIX workstations using the default DIVIMP installation will have an organizational structure that is similar to the one used here.


The DIVIMP simulation code is used to model impurity ion transport in the edge plasma region of Tokamak fusion devices. The code itself is composed of several different modules which, in general, fulfill discrete purposes. The code was written in such a way as to allow all of the basic parameters of the simulation to be changed with ease. This functional ability mandates that each DIVIMP run requires an input data file which specifies all of the options for the particular case being simulated. In addition, the companion code, OUT, produces all of the graphical output associated with the DIVIMP run. It too requires an input data file which contains descriptions of the number, type and characteristics of plots desired for the case being run. The whole process of running these codes can be most easily dealt with by placing all the necessary commands in one file called a "shell script". This file contains the series of UNIX commands that will first create a directory for the code to run in, copy all necessary files to this directory, execute the DIVIMP code, move some files to the results directory, execute OUT, move the rest of the desired files to the results directory, send the postscript files to the printer, if desired, and finally delete the temporary directory that was created for running the code.

The following document is structured in such a way as to describe the details of the process of executing the DIVIMP code. It includes a description of the files and their locations. It then describes, with some examples, the DIVIMP and OUT input data files with some suggestions on how to change the contents of these to create your own input data files. Next, there is a description of the shell scripts that actually run the code; what they are called and how they are correctly executed. Then the results are discussed; where they are stored and how to access, print or display them. Finally, some techniques of job management, including monitoring the CPU usage and number of jobs currently executing as well as how to terminate the execution of your own jobs are discussed.

For more information on actually building DIVIMP, please refer to the description and listing of the Makefiles at the end of the Source Code Summary document.

Locations of DIVIMP Files

All of the simulation codes in Toronto are laid out in the /u/progs directory tree. The DIVIMP code and related data files, results and documentation are kept in the /u/progs/div6 directory. The following is a partial list of directories in this tree and the types of files that can be found there. In general the /u/progs/div6 prefix will be installation dependent and will change from site to site. However, the rest of the directory structure should remain the same

/u/progs/div6/ DIVIMP root directory
div6 DIV source code and executable
out6 OUT source code and executable
comsrc Source code common to DIV and OUT
commons Common block declaration for DIV and OUT
data Input data files for both DIV and OUT
results Results from the DIVIMP runs
docs Documentation for DIV and OUT
shots Geometry data for various shots on various machines
eirene Version of the Eirene Neutral Code (called from DIV)
pin6 Version 6 of the PIN Neutral Code (called from DIV)
pin6coms Contains the common blocks required by pin6
bin This directory contains some shell scripts and executables that have occasionally been found to be useful when working with DIVIMP.
lib This directory can be set up to include the local libraries required by DIVIMP. Including such things as the local GHOST graphics library required by the OUT program.
/u/adas/ adas ADAS support and data files
ldh ADAS data generated by Lorne Horton at JET

What files are required and what do they do?

DIVIMP requires a variety of supporting data files and programs, some of which depend on the options selected within DIVIMP. For example, the PIN hydrogenic neutral code is required if one wants to examine the expected hydrogenic ionization given the specified background plasma conditions in DIVIMP (This hydrogenic neutral code, NIMBUS, only works in conjunction with JET geometry files - EIRENE may be used when dealing with Sonnet style geometry files.). The ADAS data files would be necessary if the ADAS atomic physics package was specified for use or if one was plotting radiative emission profiles and wished to use the data for line profiles from the ADAS database. In addition, DIVIMP requires geometry data files which specify the underlying grid that is used to tally and move the particles. These grids are stored in the shots directory and are for specific shots on specific machines. Grids are currently available for JET, ITER, Asdex Upgrade, CMOD, TdV and DIIID. Finally, DIVIMP requires input files that specify the parameter values for the case to be run and the list of plots desired. These files are described in greater detail in the following section.

The Input files: How to set up a case!

There are two input files that are edited by the user to specify the input parameters for running the case. The first is the DIVIMP input file that describes the characteristics of the specific simulation. The second is the OUT program input file that contains the information specifying what plots need to be produced. Typically, the input data files will reside in the ~/data directory for the user or in the /u/progs/div6/data directory. The names for the files are usually chosen to be somewhat descriptive of the set of cases with each separate case in a set having a different letter or number. ( e.g. jrecne35.d6i, JET Recycle Neon Series case number 35). The case name will be followed by an extension which is usually ".d6i" standing for DIVIMP version 6 Input. The OUT input files end in the file extension ".d6o" and would typically be named after the series to which they applied. (e.g. jrecnea.d6o might be used to generate plots for all of the jrecne series cases.) Some series will have a very large number of cases in them and as such may be stored in a separate directory in the data directory in order to simplify looking for case files at a later date. As the code grows and changes, the contents of these input files also change since more parameters are required for the simulation. The most recent input files will have all the parameters required to run the code. It is simply a matter of ensuring that the parameters contain values that are correct for the simulation that you want to run. There are several quantities that a user needs to set each time a case is run in order to avoid confusion. First is the title line for the case. This is the first line in the data file and generally lists the case number and series identifier as well as some particulars about the case. There is no checking done to ensure that these values have any relation to the case being run. It is simply a description that will be placed on the title of each plot produced and at the head of the output data file from the DIVIMP run. The other quantities include such things as the number of particles to be launched or injected, the background plasma specifications, and a myriad of simulation options that are described in detail in the DIVIMP and OUT reference manuals and documentation.

Executing DIVIMP: The various shell scripts

There are two commands that are used to run DIVIMP and OUT. These two commands are called "rundiv" and "runout". The rundiv shell script issues all the commands to run a DIVIMP case and the process the raw data file through the OUT program to produce the plots. The runout shell script uses an already existing raw data file and generates a selected series of plots for it. The raw data file and the OUT program running on it must be compatible versions. The raw data file consists of a record of most of the results of the DIVIMP run in a binary data format. The routine which writes this file is in the DIVIMP module iodiv.d6a and the routine which reads it in is in the OUT module ioout.o6a. If there is a discrepancy between the amount and types of data written by DIVIMP and those read by OUT then the plotted results are not reliable. This can only occur when a code change to the OUT and/or DIVIMP programs has been made that affects the raw data file. This problem can arise when trying to process very old raw data files with a newer version of OUT.

The exact format of the commands is the following:

rundiv <divimp input file> <out input file> <geometry file> <optional Edge2D file specifier>

for example:

rundiv jrecne35 jrecne1 g37943.jun0795 test

The script expects that the file jrecne35.d6i will exist and contain a valid description of the simulation parameters. Second, the file jrecne1.d6o must also exist and contain a specification for which plots are to be printed. Finally, the <geometry file> specification refers to files found in the shots sub-directory and which contain the basic geometry and magnetic field data for the grid upon which the simulation is to be run. The name of this files matches the name entered on the command line. Thus the equilibrium file is expected to be called “g37943.jun0795”. In addition, the optional specifier, “.test” in this case, instructs the script to pre-connect the background plasma file called g37943.jun0795.test to the FORTRAN unit number that is assigned for reading in the background plasma. (unit 11).

The format for the OUT shell script is similar:

runout <divimp case name> <out input file>

for example:

runout jrecne35 jrecne2

This tells the runout script to work with the raw data from case jrecne35. This file is stored in the results sub-directory in a compressed data format. The actual name of the file is jrecne35.raw.Z. This is uncompressed by the shell script and then used by OUT as it's raw data input. This file must exist. The OUT input file, "jrecne2" in this example (jrecne2.d6o), must also exist and is found in the data sub-directory.

Listings of these two shell scripts are found in the appendix.

The Output files: Contents and Meaning

A run of DIVIMP and OUT produces many more files than are typically needed. All of the files are listed, in ascending, order by the FORTRAN Unit number assigned to them in the code. All of the files are written to the results directory by the shell scripts listed above. In addition, the file name under which the information is stored is also listed. The files which may be automatically printed are listed with two additional names. The second is the name of the Postscript file that may be sent directly to the printer.

fort.6 <case name>.lim

This file contains debugging and other information about the DIVIMP run. Ancillary tables and data that might be infrequently referred to are placed here.

fort.7 <case name>.dat <case name>.ps

This contains the data file for the case describing the options selected and the results obtained for the simulation. The .ps extension file contains a printable postscript version of the data file, generated using the program a2ps.

fort.8 <case name>.raw.Z

This is the file containing the raw data from the case. Typically it is several megabytes long but is very easily compressed because many of the arrays are quite sparse. The ".Z" file extension in the name is created by the UNIX "compress" utility.

fort.9 <case name>.inp

This ancillary file contains a record of various additional aspects of the case that has been run. Among these is an echo of the input data that can be useful for debugging purposes.

fort.17 <case name>.pin

This file contains a listing of the background plasma for the DIVIMP run in a format suitable for being passed to PIN. (the hydrogenic neutral code).

fort.21 <case name>.sol

This file, if it exists, contains additional detailed output from SOL option 22 - if this option was selected to generate the background plasma.

fort.24 <case name>.pinprn

This file contains additional output from a PIN run - if such has been executed.

fort.62 <case name>.bgp

If Print option 10 has been selected inside DIVIMP, then DIVIMP generates a background plasma file of the final plasma that is being used for the case. This file can then be specified as the input to later DIVIMP cases using option 98 of the Plasma Decay, SOL, and Temperature Gradient Options. (see DIVIMP reference manual).

After DIVIMP has finished running and the above files have been transferred to the results directory (with the exception of the raw file which is transferred and compressed at the end after the OUT program has run.) the following files are created by the OUT program.

fort.6 <case name>.out

This contains a record of plots and debugging information for the run of the OUT program.

fort.9 <case name>.ing

This contains an echo of the input fed into the OUT program.

fort.26 <case name>.grp

This contains tables of numbers for the plots requested, instead of the standard plots. This is to facilitate editing of the results and processing of them through external means, such as a spreadsheet. This file is only produced if the "produce column data" option is selected in the output driver file. Note also that a postscript plot file is not produced if this file is produced.

fort.49 <case name>.plt

This file contains additional plotting information or tables for some of the plots.

POSTSCPT.LIS <case name>.psg

The file POSTSCPT.LIS is generated by the Ghost graphics package. This package of FORTRAN plotting routines which was written by the UKAEA in England is used to generate the plots for the DIVIMP runs. Details of the library can be found in the Ghost user manual. This is a postscript plot file that can be sent directly to the printer.

Monitoring Execution and Job Management

There are a few commands that are useful for monitoring the execution of cases and for controlling or halting the execution of DIVIMP cases. (Some of these commands may only apply on RS6000 computers and only if the requisite software is installed.) The first command is called "monitor". It will list which processes are currently using CPU time and the portion of CPU time that is being utilized by each process. (This is a free program available for IBM RS6000 computers. Equivalent programs are available on most UNIX based computer systems. Contact your local system administrator.)

The form of the command is the following:

monitor -top

The option -top brings up the list of processes and their CPU usage. Do not leave this running as monitor also uses CPU time. It is used to spot check the load on the computer when you are contemplating starting a case. In general, there should be no more than one or two DIVIMP cases running at any one time. To exit the monitor program, type the letter "q". It will usually take several seconds to exit.

Another useful command is "ps". This will list the processes that you are currently running. This will include DIVIMP cases as well as any other processes you might have initiated. A good form of the command is:

ps -f -u <name> Where <name> is your login name.

For example:

ps -f -u pcs

Will list all processes currently running that are owned by user pcs.

One of the columns of the output of the command is the Process ID.

For example:


pcs 8113 10416 0 Jun 13 pts/0 0:04 -ksh

The process ID number of the "ksh" process for user pcs is 8113. This number is important if one wants to "kill" a job before it has completed executing.

In order to kill a process, one would use the kill command.

In the following example the command "ps -f -u david" was used to obtain the following table of processes.

david 4280 15793 0 09:57:53 hft/1 0:01 xbiff
david 5341 5399 0 14:34:59 - 0:00 ksh
david 5399 1632 0 11:32:11 - 0:00 ksh
david 8792 11709 0 14:00 pts/1 1:06 wp
david 13293 5341 53 14:35:24 - 140:11 /u/progs/div6/div6/div6O
david 15574 1 0 09:58:32 - 0:05 aixterm
david 15973 13471 0 09:57:49 hft/1 0:06 mwm
david 15992 9586 53 17:47:27 - 9:48 /u/progs/div6/div6/div6O
... ... ... ... ... ... ... ...

As can be seen from the output there are two DIVIMP processes currently running. These are both indicated by the CMD column which shows the command being executed "/u/progs/div6/div6/div6O". If one wanted to kill the second of these processes, read the PID from the table (which is 15992). Then use it in one of the following three forms of the kill command.

kill 15992

This tells the program to terminate, if the program has a serious bug it may ignore this signal.

kill -9 15992

This tells the operating system to kill the program immediately, no matter what it's current status. This is almost certain to cause the program to stop.

Both of the above forms do not let the program terminate nicely. Neither wrap up processing nor file output will be completed. An alternative command is the following.

kill -USR1 15992

This will send the USR1 signal to the DIVIMP process. Code has been added to DIVIMP to trap this signal and do some completion processing before exiting. Results will be unusable except for debugging purposes, but by using this method it may be possible to determine what was going on in DIVIMP when the signal was received, based on the type and amount of data printed out.

Another useful command, which is used to clean up the results directory, is called clean. This is a simple shell script which will delete the ancillary results files for a case, keeping only the ".dat" file from FORTRAN unit 7 and the compressed raw data file. This is sufficient information to regenerate various plots or other types of information. It is not usually enough for debugging. These are the files that are archived for semi-permanent storage, in case they are required at a later time for further analysis. (Though changes in DIVIMP and OUT may supersede the format of the raw data file. If it frequently occurred that old results were needed, then a version number system could be implemented whereby the IO modules of DIVIMP and OUT would know what to read from the raw data file. However, at this time, this feature has not proven to be worth implementing.)

The form of the command is:

clean <case name>

For example:

clean jrecne35

The above will delete all the extra files associated with jrecne35, except jrecne35.dat and jrecne35.raw.Z . There is also a more general version of the clean command available. It should not be made available to all users. This command, "cleanall", will delete all ancillary files for all cases currently in the results directory. It will leave only the two files for each case that the clean command leaves. This command is most useful just prior to backing up the entire results directory. After the remaining files have been copied to tape, they too can be deleted and a great deal of space freed for further modeling. A copy of the "clean" and “cleanall” shell scripts is included in the Appendix.

Appendix A : Shell Scripts