Programmer's Manual - OdonataResearchLLC/NASTRAN-95 GitHub Wiki

The Programmer's Manual is currently a place to document the existing code base as it is audited and modernized. It also serves as a running commentary on ideas for modernization of the data structures as well as the code base in general.

Plan of Attack

Make the minimum updates necessary to run all of the demonstration input.
Modernize the program level code in the mds directory. Treat the code in mis that compiles to libnastran.a as fixed to the greatest extent possible. There will be modifications from the mds level, for example data structures, that will drive changes in the mis code. But, the intent is not to initiate any modernization at the mis level.
Once the program level code is modernized, modernize the organization and data structures in the mis code to use modern data structures, facilitate extensions, and use 3rd party libraries (i.e. linear algebra, OpenMP, OpenCL).
Extend and Improve

Observations

Hollerith constants are used extensively throughout the code base and need to be replaced with characters.
Integers are frequently used to store CHARACTER*4 data and this is causing issues. It may be an issue with using a 64-bit compiler, but it might as well be fixed now.
Machine specific code needs to be replaced with platform independent code.
Need to simplify memory management and replace custom management routines with standard Fortran 95 methods.

Block Data

The legacy link instructions pull the block data objects out of the NASTRAN library with ar and compile them with the main program. This was required so that the initialized data was preserved at the top level. In NASTRAN-95, the block data files were moved to the BD directory and compiled separately from the NASTRAN library. This solution negated having to pull the objects out of the NASTRAN library. The correct solution is to define the block data in modules as the code is migrated to Fortran 95.

Machine Constants

The machine constans are defined in subroutine btstrp. The constants are communicated using the following common blocks.

SYSTEM
LHPWX
MACHIN
CHMACH

The following subroutines should be reviewed when NASTRAN is ported to a new machine.

PRTPRM
SDCMPS
SDR2E
UPCASE

In common block MACHIN, any subroutine that uses MACHX instead of MACH contains machine constants that are used locally.

COSMIC/NASTRAN Supported Machines

MACH	Hardware	OS	Supported
1	DUMMY		NO
2	IBM	MVS	YES
3	UNIVAC	FTN	NO
4	CDC	FTN5	NO
5	DEC-VAX	VMS	YES
6	DEC-MIPS	ULTRIX	YES
7	SUN	SOLARIS	YES
8	IBM RS6000	AIX	YES
9	HP	HP-UX	YES
10	SGI	IRIX	YES
11	MACINTOCH		NO
12	CRAY	UNICOS	NO
13	CONVEX		NO
14	NEC		NO
15	FUJITSU		NO
16	SUN	SUNOS	YES
17	AMDAHL		NO
18	PRIME		NO
19	PC	MS-DOS	NO
20	DUMMY		NO
21	DEC-ALPHA	OPENVMS	YES
22	DEC-ALPHA	OSF	YES

Length of NASTRAN I/O Buffer

MACH	Hardware	OS	SYSBUF
1	DUMMY		200
2	IBM	MVS	4100
3	UNIVAC	FTN	871
4	CDC	FTN5	1042
5	DEC-VAX	VMS	1028
6	DEC-MIPS	ULTRIX	1028
7	SUN	SOLARIS	1028
8	IBM RS6000	AIX	1028
9	HP	HP-UX	1028
10	SGI	IRIX	1028
11	MACINTOCH		1028
12	CRAY	UNICOS	2052
13	CONVEX		1028
14	NEC		2052
15	FUJITSU		2052
16	SUN	SUNOS	1028
17	AMDAHL		1028
18	PRIME		1028
19	PC	MS-DOS	1028
20	DUMMY		1028
21	DEC-ALPHA	OPENVMS	1028
22	DEC-ALPHA	OSF	1028

Fortran Unit for Input Data and Printed Output

INTP : Fortran unit for input data
OUTTAP : Fortran unit for printed output

MACH	Hardware	OS	INTP	OUTTAP
1	DUMMY		5	6
2	IBM	MVS	5	6
3	UNIVAC	FTN	5	6
4	CDC	FTN5	5	6
5	DEC-VAX	VMS	5	6
6	DEC-MIPS	ULTRIX	5	6
7	SUN	SOLARIS	5	6
8	IBM RS6000	AIX	5	6
9	HP	HP-UX	5	6
10	SGI	IRIX	5	6
11	MACINTOCH		5	6
12	CRAY	UNICOS	5	6
13	CONVEX		5	6
14	NEC		5	6
15	FUJITSU		5	6
16	SUN	SUNOS	5	6
17	AMDAHL		5	6
18	PRIME		5	6
19	PC	MS-DOS	5	6
20	DUMMY		5	6
21	DEC-ALPHA	OPENVMS	5	6
22	DEC-ALPHA	OSF	5	6

Number of Lines/Page and Words/Input Card

NLPP : Number of lines printed per page
NWPIC : Number of words per input card, used only in XGPIBS

MACH	Hardware	OS	NLPP	NWPIC
1	DUMMY		50	0
2	IBM	MVS	55	18
3	UNIVAC	FTN	42	8
4	CDC	FTN5	55	18
5	DEC-VAX	VMS	55	18
6	DEC-MIPS	ULTRIX	55	18
7	SUN	SOLARIS	55	18
8	IBM RS6000	AIX	55	18
9	HP	HP-UX	55	18
10	SGI	IRIX	55	18
11	MACINTOCH		55	18
12	CRAY	UNICOS	55	9
13	CONVEX		55	18
14	NEC		55	0
15	FUJITSU		55	0
16	SUN	SUNOS	55	0
17	AMDAHL		55	0
18	PRIME		55	0
19	PC	MS-DOS	55	0
20	DUMMY		55	0
21	DEC-ALPHA	OPENVMS	55	18
22	DEC-ALPHA	OSF	55	0

Number of Bits/Character and Bits/Word

NBPC : Number of bits per character
NBPW : Number of bits per word

MACH	Hardware	OS	NBPC	NBPW
1	DUMMY		6	36
2	IBM	MVS	8	32
3	UNIVAC	FTN	9	36
4	CDC	FTN5	6	60
5	DEC-VAX	VMS	8	32
6	DEC-MIPS	ULTRIX	8	32
7	SUN	SOLARIS	8	32
8	IBM RS6000	AIX	8	32
9	HP	HP-UX	8	32
10	SGI	IRIX	8	32
11	MACINTOCH		8	32
12	CRAY	UNICOS	8	64
13	CONVEX		8	32
14	NEC		8	64
15	FUJITSU		8	64
16	SUN	SUNOS	8	32
17	AMDAHL		8	32
18	PRIME		8	32
19	PC	MS-DOS	8	32
20	DUMMY		8	32
21	DEC-ALPHA	OPENVMS	8	32
22	DEC-ALPHA	OSF	8	32

Precision and Record Length

IPREC : Precision; single precision = 1; double precision = 2
RECL : Direct file record length (used in Fortran OPEN statement); by words = 1; by byte = NCPW
QP : REAL*16 precision flag; YES = 1; NO = 0

MACH	Hardware	OS	IPREC	RECL
1	DUMMY		2	0
2	IBM	MVS	2	4
3	UNIVAC	FTN	2	1
4	CDC	FTN5	1	1
5	DEC-VAX	VMS	2	1
6	DEC-MIPS	ULTRIX	2	1
7	SUN	SOLARIS	2	4
8	IBM RS6000	AIX	2	4
9	HP	HP-UX	2	4
10	SGI	IRIX	2	1
11	MACINTOCH		2	0
12	CRAY	UNICOS	1	8
13	CONVEX		2	4
14	NEC		1	0
15	FUJITSU		1	0
16	SUN	SUNOS	2	0
17	AMDAHL		2	0
18	PRIME		2	0
19	PC	MS-DOS	2	0
20	DUMMY		2	0
21	DEC-ALPHA	OPENVMS	2	1
22	DEC-ALPHA	OSF	2	0

Fortran Units for Punched Data

LPCH : Fortran unit for punched output
LDICT : Fortran unit for restart dictionary punch

MACH	Hardware	OS	LPCH	LDICT
1	DUMMY		7	3
2	IBM	MVS	7	7
3	UNIVAC	FTN	1	3
4	CDC	FTN5	7	7
5	DEC-VAX	VMS	1	4
6	DEC-MIPS	ULTRIX	1	4
7	SUN	SOLARIS	1	4
8	IBM RS6000	AIX	1	4
9	HP	HP-UX	1	4
10	SGI	IRIX	1	4
11	MACINTOCH		1	4
12	CRAY	UNICOS	1	4
13	CONVEX		1	4
14	NEC		1	4
15	FUJITSU		1	4
16	SUN	SUNOS	1	4
17	AMDAHL		1	4
18	PRIME		1	4
19	PC	MS-DOS	1	4
20	DUMMY		1	4
21	DEC-ALPHA	OPENVMS	1	4
22	DEC-ALPHA	OSF	1	4

Numeric Range for Single Precision Real Numbers

Used only by RCARD, RCARD2, XRCARD, and YRCARD. Only HIGHPW is specified, LOWPW = 1 - HIGHPW.

MACH	Hardware	OS	HIGHPW
1	DUMMY		38
2	IBM	MVS	75
3	UNIVAC	FTN	38
4	CDC	FTN5	321
5	DEC-VAX	VMS	38
6	DEC-MIPS	ULTRIX	38
7	SUN	SOLARIS	38
8	IBM RS6000	AIX	38
9	HP	HP-UX	38
10	SGI	IRIX	38
11	MACINTOCH		38
12	CRAY	UNICOS	2465
13	CONVEX		38
14	NEC		0
15	FUJITSU		0
16	SUN	SUNOS	0
17	AMDAHL		0
18	PRIME		0
19	PC	MS-DOS	0
20	DUMMY		0
21	DEC-ALPHA	OPENVMS	38
22	DEC-ALPHA	OSF	0

Floating Point Underflow and Maxinum Files in `NASCAR`

NUDFLW : Floating number underflow control, used only by FQRW and FQRWV MXFL : Maxinum files MAXFIL can request via the NASTRAN card, used only by NASCAR

MACH	Hardware	OS	NUDFLW	MXFL
1	DUMMY		16	50
2	IBM	MVS	16	50
3	UNIVAC	FTN	18	49
4	CDC	FTN5	14	75
5	DEC-VAX	VMS	8	75
6	DEC-MIPS	ULTRIX	16	75
7	SUN	SOLARIS	16	75
8	IBM RS6000	AIX	16	75
9	HP	HP-UX	16	75
10	SGI	IRIX	16	75
11	MACINTOCH		16	75
12	CRAY	UNICOS	16	75
13	CONVEX		16	75
14	NEC		16	75
15	FUJITSU		16	75
16	SUN	SUNOS	16	75
17	AMDAHL		16	75
18	PRIME		16	75
19	PC	MS-DOS	16	75
20	DUMMY		16	75
21	DEC-ALPHA	OPENVMS	9	75
22	DEC-ALPHA	OSF	16	75

Shift Counts

KSHIFT : Shift counts used in a divide to convert a GINO LOC returned from SAVPOS to GINO block number, used in EMA.

MACH	Hardware	OS	KSHIFT
1	DUMMY		1
2	IBM	MVS	4096
3	UNIVAC	FTN	4096
4	CDC	FTN5	262144
5	DEC-VAX	VMS	4096
6	DEC-MIPS	ULTRIX	4096
7	SUN	SOLARIS	4096
8	IBM RS6000	AIX	4096
9	HP	HP-UX	4096
10	SGI	IRIX	4096
11	MACINTOCH		4096
12	CRAY	UNICOS	4096
13	CONVEX		4096
14	NEC		0
15	FUJITSU		0
16	SUN	SUNOS	0
17	AMDAHL		0
18	PRIME		0
19	PC	MS-DOS	0
20	DUMMY		0
21	DEC-ALPHA	OPENVMS	4096
22	DEC-ALPHA	OSF	0

Mantissa Bits

MTISA : Used on in SDCMPS

MACH	Hardware	OS	SP	DP
1	DUMMY		0	00
2	IBM	MVS	24	26
3	UNIVAC	FTN	27	60
4	CDC	FTN5	48	96
5	DEC-VAX	VMS	23	55
6	DEC-MIPS	ULTRIX	23	55
7	SUN	SOLARIS	23	52
8	IBM RS6000	AIX	23	55
9	HP	HP-UX	23	55
10	SGI	IRIX	23	55
11	MACINTOCH		23	55
12	CRAY	UNICOS	48	96
13	CONVEX		23	52
14	NEC		48	96
15	FUJITSU		48	96
16	SUN	SUNOS	23	55
17	AMDAHL		23	55
18	PRIME		23	55
19	PC	MS-DOS	0	00
20	DUMMY		0	00
21	DEC-ALPHA	OPENVMS	23	55
22	DEC-ALPHA	OSF	0	00

File Control Block (FCB)

The File Control Block (FCB) is used by the NASTRAN program code in the mds directory. The main issue with the FCB array is that it is an integer array, but elements 13 and 14 are used to store character data. The format of the FCB was taken from the file mis/gnfiat.f. Fortran INTEGER FCB COMMON / FCB / FCB(17,MAXFCB)

Index	Description	Notes
1	Open Flag (0 - Read, 1 - Write)
2	Buffer Address
3	Current Logical Record (CLR)
4	Current Block Number
5	First Block Number on External File
6	Last Block Number on External File
7	Number of Blocks Allocated to this File
8	Flag for Writing the First Column on File (0-NO, 1-YES)
9	Index to First In-Memory Block
10	Index to Last In-Memory Block
11	Index to Current In-Memory Block
12	Original Buffer Address (ON Open)
13,14	DMAP File Name	Implicit coercion of CHARACTER*4 data to each integer element
15	Open Flag for External File
16	Total Number of Strings in this Matrix
17	Total Number of Terms in this Matrix

MSGX Common Block

The MSGX common block in the mis directory causes a segmentation fault trying to implicitly convert integer to character data in SUBROUTINE MESAGE. Fortran COMMON /MSGX / N,M,MSG(4,1)

Variable	Implicit Type	Data Type	Description
N	Integer	Integer	Current number of messages stored
M	Integer	Integer	Maximum number possible
MSG(1,I)	Integer	Integer	Number
MSG(2,I)	Integer	Integer	Parameter
MSG(3,I)	Integer	`Character*4`	Name(1:4)
MSG(4,I)	Integer	`Character*4`	Name(5:8)