Fortran 90 for Beginners

Download free Fortran 90 Programming language course material, tutorial training, a PDF file by Tadziu Hoffmann & Joachim Puls.

Table of contents

• Literature
• Internet resources
• Compiler documentation
• Fortran Syntax
• Data types
• Expressions
• Loops
• Decisions
• Input/Output
• Arrays
• Subroutines and functions
• Modules

Introduction to Fortran for beginners

A FORTRAN program is primarily a sequence of instructions in ASCII characters. The file containing these instructions must end in .f, .F (or .f90 or .F90 if Fortran 90 has followed for writing files).

In FORTRAN 77, the lines are limited to 80 characters. The first 6 characters have a special status:

A line corresponding to a normal statement starts at character 7 (after 6 white characters).
A character "c" or "!" in the first column means that the line is a comment line.
Any character in the 6th column indicates that the line is the continuation of the previous line.
Uppercase and lowercase letters are undifferentiated in Fortran.
A Fortran program starts with a "program" statement and ends with an "end" statement.

Basics

In Fortran 90, we can write from the first character. Comments start with one! Lines can exceed 80 characters.

Essentially, there is upstream compatibility between the two versions of Fortran, ie a code written in Fortran 77 can be compiled fortran 90/95. However, this does not concern the writing format described above. If we follow the format fortran 77, we will name the file program.f. If we follow fortran 95, program.f90. In any case, the compilation will be done with the same command g95.