PREREQUISITES:

	-  A fortran compiler, gfortran will do. On Linux, Windows (mingw) and
	   on Android using CCTools.
	
	-  GNU make.


HOW TO USE:

	1. Run make in "src" dir.
	
	2. Set nasthome enviroment variable pointing to the nastran root 
	   directory. Avoid the "-" character, it will break nastran.
	
	3. Place your problem file in the "test" directory. You'll finde 
	   some in the "inp" directory.
	
	4. Run from there ..\bin\nastran or on windows  ..\bin\nastran.bat xxx
	   where xxx is your problem file (without the file extension). For
	   Android have a look at the android.sh script. For Android you have
	   to link the program statically, otherwise it will segfault.


ISSUES:

	-  This is really old stuff, unmaintained for over 20 years. Expect
	   something will break.
	
	-  There are some features missing in comparision to the commercial
	   Nastran versions. Some entities have different names.
	   E.g.:  RBE3 <=> CRBE3
	         CHEXA <=> CIHEX1
	
	-  The CQUAD4 and especially the CIHEX1 (the Cosmic CHEXA) suffers from
	   shear locking. Two test cases are profided in the test directory. 
	   This could be improved by implementing selective reduced integration
	   as it is described in the Fourteenth NASTRAN Users' Colloquium
	   (p. 28ff) and in: http://paginas.fe.up.pt/~rnatal/paper.pdf.
	
	-  There seems to be no corner stress output for the CQUAD4 element,
	   whereas it is calculated within the SQUD42 subroutine.
	
	-  There are no optimization capabilities, exept the FSD method as
	   shown in the NASTRAN DEMONSTRATION PROBLEM NO. D01-16-1A
	
	-  There is no predefined binary result output, as some users may be
	   used to PARAM,POST. Nevertheless it is possible to write an op2 file
	   via DMAP alters, which then can be read by common post-processing
	   software. Basically insert 
	   OUTPUT2  "DATABLOCK",,,,//C,N,0/C,N,11////C,N,*MSC* $
	   after the OPF DMAP statement.
	

