Update and Availability of the Two-dimensional Method-of-Characteristics Solute Transport Model Program for Prime Computers.



             UNITED STATES DEPARTMENT OF THE INTERIOR
                        GEOLOGICAL SURVEY
                        RESTON, VA. 22092

In Reply Refer To:                            November 28, 1983
EGS-Mail Stop 411


GROUND WATER BRANCH TECHNICAL MEMORANDUM NO. 84.01

Subject:  GROUND WATER--Update and Availability of the Two-
                        dimensional Method-of-Characteristics
                        Solute Transport Model Program for Prime
                        Computers.

The attached set of "update notes" documents a number of revisions
that have been made recently to the two-dimensional solute-
transport model documented in Techniques of Water-Resources
Investigations, Book 7, Chapter C2.  The modified code will
generally yield more accurate results, and it is recommended that
all users of this model modify their source code accordingly.

The updated source code of the subject model runs successfully on
Prime if it is compiled with the F77 compiler using no options.
The -F option only slightly increases the accuracy, but also
increases the CPU time by over 5 percent, so it is probably not
necessary or desirable for most problems.  Our initial experience
in using this program on the Reston Prime indicates that if the
decimal point is omitted from a G-format input data field, as is
used for much of the input data, then the Prime will not fill in
trailing blanks as trailing zeros; consequently, it will place the
decimal at a point other than anticipated.

Until the Prime telecommunication network becomes operational,
copies of the updated source code card images can be obtained by
running the following job on the USGS Re-1 Amdahl computer in
Reston, Virginia:

//----JOB----
/*JOBPARM CARDS=800, LINES=5
/*ROUTE PUNCH RMTxxx
//PROCLIB DD DISP=SHR, DSN=SWB.PROCLIB
//   EXEC CARDPCH, UDS='VG46ANN.MOCP.FORT/', LIST=1
//

The xxx should be replaced by the Amdahl remote-terminal number of
the Prime site at your respective Districts.  This job sends
punched-card images to the Prime RJE facility at the specific
site.  Installation-specific procedures should be followed to
receive the card images and move them to an appropriate user
directory (refer to DIS Newsletter, Vol. 1, No. 6, November 1983)
or consult your system administrator.  The source code also could
be sent by means of TSO or WYLBUR.

If you have any trouble moving the source code or compiling,
loading or running the computer program, please contact Ren Jen
Sun of the Ground Water Branch, on FTS: 928-6904.



                              (s) Eugene P. Patten
                              Chief, Ground Water Branch

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