Fortran 68: The Legacy and Power of This Classic Programming Language

Fortran 68, a relatively lesser-known version of the famous Fortran programming language, holds an interesting place in the evolution of computing. Released as an update to Fortran IV, Fortran 68 sought to modernize the language and improve its capabilities for handling more complex computational tasks. In this article, we’ll explore the features of Fortran 68, its significance in the history of programming, and give you a taste of how it works with some practical examples. So buckle up, let’s take a trip back in time!

What Is Fortran 68?

Fortran 68, also known as Fortran 68, was introduced as part of the evolution of the Fortran language in the late 1960s. It represented an attempt to adapt Fortran for the growing demands of scientific and engineering computing. While not as widely used as its predecessor, Fortran IV, or its successors like Fortran 77, Fortran 68 introduced important features that would later shape modern programming languages.

One of the major aims of Fortran 68 was to offer a more structured and flexible approach to programming compared to its predecessors. It included enhanced capabilities for handling data, control structures, and modular programming. Despite its limited adoption, Fortran 68 made a lasting impact on the development of later programming languages.

The Features of Fortran 68

Fortran 68, though not as popular as later versions, included several noteworthy features:

• Improved Syntax: Fortran 68 enhanced the syntax of the language, making it more readable and structured than previous versions. It introduced new control structures and features that allowed for better program flow and organization.
• Advanced Data Handling: Fortran 68 included improvements to data types and arrays, making it more efficient for managing large datasets commonly used in scientific computations.
• Support for Structured Programming: Fortran 68 was one of the early adopters of structured programming concepts, which later became central to modern software development practices.
• Modular Design: With the introduction of modular programming features, Fortran 68 made it easier to organize code into reusable modules, which was a precursor to object-oriented programming.

Fortran 68 vs. Fortran IV

When compared to Fortran IV, Fortran 68 represented a significant leap forward in terms of design and capabilities. While Fortran IV was widely used in the scientific community, it had certain limitations in terms of modularity, error handling, and data structures. Fortran 68 addressed these issues by introducing better support for structured programming, making it easier to write complex programs.

Fortran IV was known for its simplicity and efficiency, but it lacked the flexibility needed for larger projects. Fortran 68 attempted to fix these issues, providing a better framework for managing complex data structures and increasing the overall robustness of the language. However, despite these improvements, Fortran 68 never gained the same widespread adoption as Fortran IV or later versions like Fortran 77.

Fortran 68 Example: A Simple Program

Let’s take a look at a simple example written in Fortran 68 to give you an idea of how the language looked and functioned. Below is a simple program that calculates the factorial of a number:

      PROGRAM FACTORIAL
      INTEGER N, FACTORIAL, I
      PRINT *, "Enter a number: "
      READ *, N
      FACTORIAL = 1
      DO I = 1, N
         FACTORIAL = FACTORIAL * I
      END DO
      PRINT *, "The factorial of ", N, " is ", FACTORIAL
      END

This basic program demonstrates how Fortran 68 could handle user input and simple arithmetic operations, such as calculating the factorial of a given number. It uses a loop to iterate through the numbers from 1 to N, multiplying them together to compute the factorial.

Fortran 68 Example: Working with Arrays

In this next example, let’s look at how Fortran 68 can work with arrays. Arrays were essential for handling large datasets in scientific computing, and Fortran 68 allowed for more advanced data handling techniques. Below is an example of using arrays in Fortran 68 to store and sum a series of numbers:

      PROGRAM ARRAY_SUM
      INTEGER ARRAY(10), I, SUM
      SUM = 0
      PRINT *, "Enter 10 numbers:"
      DO I = 1, 10
         READ *, ARRAY(I)
         SUM = SUM + ARRAY(I)
      END DO
      PRINT *, "The sum of the entered numbers is ", SUM
      END

This program demonstrates how Fortran 68 could manage arrays and perform simple operations on them. It reads 10 numbers from the user, stores them in an array, and calculates their sum. This is a basic example of how Fortran 68 could be used for numerical computations, a common use case for the language.

Why Was Fortran 68 Not Widely Adopted?

While Fortran 68 introduced many useful features, it ultimately failed to gain widespread adoption in the programming community. One of the primary reasons for this was the fact that Fortran 77, released shortly after Fortran 68, offered many of the same features but with greater compatibility and broader industry support.

Fortran 77 improved upon the ideas introduced in Fortran 68, adding better support for structured programming, modularity, and improved error handling. As a result, Fortran 68 quickly became obsolete, with most programmers moving to Fortran 77, which became the de facto standard for scientific computing in the 1970s and 1980s.

Another factor in Fortran 68's limited adoption was the complexity of the language compared to Fortran IV. Fortran 68 required a more disciplined approach to programming, which made it more difficult for beginners to pick up, while Fortran IV’s simplicity made it more accessible to a broader audience.

Conclusion: The Legacy of Fortran 68

While Fortran 68 may not have had the same lasting impact as Fortran 77 or Fortran IV, it still played a crucial role in the evolution of programming languages. It introduced important concepts like structured programming, modularity, and improved data handling, which laid the groundwork for future programming languages.

Today, Fortran continues to be used in many scientific and engineering applications, and the influence of Fortran 68 can still be seen in modern Fortran versions. So, the next time you write a program in Fortran, take a moment to appreciate the history behind the language and the many versions that have come before.