FORTRAN 90 FOR THE FORTRAN 77 PROGRAMMER
The programming language FORTRAN is the principal language for
scientific and technical computations. It was developed originally in
1954 and has been revised several times, to FORTRAN IV and Fortran 77.
It has recently been carefully revised, resulting in a modern and
powerful language, Fortran 90.
The intent with this new standard is to make Fortran into a useful and
efficient language for the scientific and technical computations also
towards the end of this decade. The new version contains powerful new
features for the treatment of vectors and matrices, several new
possibilities to specify the precision, access to environment
parameters, intrinsic functions for manipulating floating point
numbers, internal procedures and new specifications for storage and
interfacing. In addition there is a new improved layout of the source
code, new conditional statements, recursion and dynamic memory
allocation. Nothing was removed, so Fortran 90 contains the whole of
Fortran 77, but offers both easier programming and improved security.
An important requirement at the introduction of a new language is
nowadays that the language should be efficient also on parallel
systems. This tutorial therefore contains an Appendix on the recent
proposed addition to Fortran, High Performance Fortran.
This tutorial assumes that the reader is experienced in Fortran 77. Those
parts of Fortran 90 that are already in Fortran 77 are not discussed
here. The many programming examples and user exercises illustrate the
programming technique and available commands, and makes it easy to get
started with writing programs using the new facilities in Fortran 90.
All examples have been tested on Sun SPARC (UNIX) and DEC Station
(ULTRIX), and on IBM PC with MS-DOS 5 and 6.2.
Bo Einarsson 
Yurij Shokin
Last modified: 27 January 1996
boein@nsc.liu.se