FTN File – What is .ftn file and how to open it?

FTN File Overview

FTN files, short for Fortran Source Code Files, primarily contain source code written in the Fortran programming language. Fortran (short for Formula Translation) is a high-level programming language designed specifically for scientific and numerical computing. It is widely used in various scientific disciplines, including mathematics, physics, engineering, and computer science. FTN files serve as the source files for Fortran programs, containing the instructions and data structures necessary for the program’s execution.

Technical Details

FTN files are plain text files that adhere to the Fortran language syntax. They typically consist of program statements, variable declarations, constants, and mathematical expressions. The file structure follows a hierarchical organization, with code blocks enclosed within parentheses or curly braces. FTN files may also include comments, which provide annotations and explanations to enhance code readability and understanding. Once created, FTN files can be compiled using a Fortran compiler, which translates the source code into machine-readable instructions (object code). The resulting object code can then be linked with other program components to create an executable program.

Opening FTN Files with Text Editors

FTN files contain source code written in the Fortran programming language. Text editors, such as Notepad++, Sublime Text, or Atom, are capable of opening and editing FTN files. They provide basic functionality for viewing and editing the code, including syntax highlighting and indentation. To open an FTN file in a text editor, simply navigate to the file in the file explorer, right-click on it, and select “Open with” > “Choose another app.” From the list of available applications, select the desired text editor.

Compiling and Running FTN Files

To execute FTN files, they need to be compiled into executable programs. Fortran compilers, such as gfortran (part of the GNU Compiler Collection) or the Intel Fortran Compiler, are required for this purpose. The specific compilation command may vary depending on the compiler being used. Generally, the command format is:


compiler -o output_file input_file.ftn


where compiler is the Fortran compiler path, output_file is the name of the executable file to be generated, and input_file.ftn is the FTN source code file. Once compiled, the executable file can be run by typing its name in the command prompt or by double-clicking on it in the file explorer.

FTN: Fortran Source Code File

The .FTN file extension denotes a Fortran Source Code File. Fortran, an acronym for FORmula TRANslation, is a general-purpose, high-level programming language developed by IBM in the late 1950s. It is primarily used for scientific and engineering applications due to its ability to efficiently handle complex mathematical calculations. The .FTN file contains the source code written in Fortran programming language. It includes statements, declarations, and other instructions that define the program’s logic and functionality.

The .FTN file serves as the initial blueprint for the program. It is typically written in plain text using a text editor or an integrated development environment (IDE) specifically designed for Fortran development. The source code is then compiled using a Fortran compiler, which translates it into executable machine code that the computer can understand and execute. The compiled code is usually stored in a separate file with a different file extension, such as .exe or .dll.

The .FTN file is crucial for maintaining the program’s source code and making modifications as needed. It allows programmers to debug the program by identifying and fixing errors in the logic or syntax. Additionally, the source code can be easily shared with other programmers for collaboration or code review, fostering knowledge exchange and ensuring code quality.

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