ISO/IEC 1539 is a multipart International Standard; the parts are published separately. This publication,
ISO/IEC 1539-1, which is the ?rst part, speci?es the form and establishes the interpretation
programs expressed in the base Fortran language. The purpose of this part of ISO/IEC 1539 is to
promote portability, reliability, maintainability, and e?cient execution of Fortran programs for use on
variety of computing systems. The second part, ISO/IEC 1539-2, de?nes additional facilities for the
manipulation of character strings of variable length. The third part, ISO/IEC 1539-3, de?nes a standard
conditional compilation facility for Fortran. A processor conforming to part 1 need not conform to
ISO/IEC 1539-2 or ISO/IEC 1539-3; however, conformance to either assumes conformance to this part.
Throughout this publication, the term “this standard” refers to ISO/IEC 1539-1.