Programming efficient code to solve numerical challenges involves various complexities. Therefore, significant coding experience is essential to resolve syntax errors and achieve accurate results. This article introduces a structured format designed to help coders minimize common errors, promoting accurate and straightforward solutions.
Although this article focuses on coding in FORTRAN, the approach presented is applicable to other programming languages as well. A professional coder understands that the complexity of any code lies in its algorithm design, which remains fundamentally language-agnostic. This methodology is organized into eleven steps, each accompanied by explanatory comments marked with an exclamation sign (!). The initial comments divide the program into distinct segments. Throughout this article, we briefly outline the purpose of each step. It is recommended to replicate these explanatory comments, similar to guideposts, within the program and then proceed with coding step-by-step, following the provided guidelines. This approach has been tested by students at various stages of their programming projects. Its proven effectiveness inspired us to share it to help researchers improve coding speed and accuracy.
At first glance, coding in MATLAB, which does not require variable definition, may seem more straightforward. However, the key advantage of low-level languages lies in their ability to define variables explicitly and use the implicit none command, effectively overriding FORTRAN’s default settings. This capability enables optimal definition of array dimensions, helping to prevent issues related to insufficient virtual memory, while also enhancing the overall speed of program execution.
!******************************************************************************************
! Variables Definition
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Using uninitialized variables can lead to significant issues in your program. It is essential to initialize all variables before use; otherwise, the compiler may retrieve residual data from a previous program that occupied the same memory segment. This can result in unpredictable behavior and difficult-to-debug errors in your program.
!******************************************************************************************
! Giving Zero to variables
!******************************************************************************************
For variables expected to change values between consecutive runs—especially when the program's goal is to assess variations in these parameters—it is important that they be defined by the user. This approach ensures that the program can be thoroughly tested and evaluated under different scenarios and conditions.
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! Inputs
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A helpful approach is to input each variable in both numerical and character formats. This allows the numerical format to be used for calculations, while the character format verifies variable names. For example, E and freq are processed as real numbers, whereas EE and freqf represent the same values in character format. This distinction is recognized and managed by the compiler.
Real E , freq
Character*30 EE, freqf, filename1
write(*,'(/,2x,a,\)') ' Enter the Energy value : '
read(*,*)E
write(*,'(/,2x,a,\)') ' Again : '
read(*,*)EE
write(*,'(/,2x,a,\)') ' Enter the frequency value : '
read(*,*)freq
write(*,'(/,2x,a,\)') ' Again : '
read(*,*)freqf
This section highlights an important consideration: optimizing the use of output files. Effective utilization can, firstly, improve the processing speed of these files and, secondly, ensure that output information is systematically organized. To achieve this, it is essential to generate file names based on the input information. This straightforward practice can lead to significant improvements in both the efficiency and organization of output data.
!******************************************************************************************
! Determination of Filenames and Opening Files
!******************************************************************************************
Additionally, when results are represented graphically, it is preferable to save the file with a .plt extension, compatible with Tecplot software. Tecplot is feature-rich and allows for easy graph generation with a single click on the file icon.
The // operator is used for concatenating two character expressions, while the trim() function removes unused characters from a character field. For example, these techniques could be applied to a graph illustrating temperature variations over time at a specified pulse energy and frequency.
filenameTt = 'E_'//trim(EE)//'f_'//trim(freqf)//'T_t.plt'
open(1,file=filenameTt)
It is crucial to centralize all of the program’s values in this section. Additionally, organizing them in a logical and readable sequence is essential for easy management and control.
!******************************************************************************************
! Constants
!******************************************************************************************
Minimizing the number of entries in an array does not necessarily reduce program execution time or decrease memory errors. Therefore, optimizing array allocation is essential. In general, it is preferable to avoid using arrays for problem-solving unless absolutely necessary.
!******************************************************************************************
! Arrays Allocation
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Initializing arrays, just as with variables, is essential. A recommended approach is to use the forall command to set all elements of the array to zero. This ensures each element is properly initialized before any further operations, helping to prevent unexpected behaviors due to uninitialized elements.
!******************************************************************************************
! Giving Zero to Arrays
!******************************************************************************************
It is crucial for the user to verify the accuracy of all input values before executing the main segment of the program. To facilitate easy monitoring, it is recommended to display each variable name alongside its corresponding value. This allows the user to efficiently review and confirm the accuracy of the input before proceeding with the main operation of the program.
!******************************************************************************************
! Printing Constants and Inputs
!******************************************************************************************
In this section, we precisely establish the boundary conditions and define the problem-solving algorithm, ensuring that both are presented in a clear and straightforward manner.
!******************************************************************************************
! Main Block of the Program
!******************************************************************************************
Although results are typically printed in a separate section, there are instances where it is necessary to store data directly into files within the main segment of the program. Carefully choosing the location for output retrieval within the program can help prevent insufficient virtual memory errors in most cases and, at times, significantly increase execution speed—occasionally by an order of magnitude.
!******************************************************************************************
! Printing Results
!******************************************************************************************
At first glance, it may seem that leaving files opened at the start of a program, poses no issues. However, experience shows that to prevent potential complications, especially from interference in subsequent runs, it is best to close files upon completion of their tasks.
!******************************************************************************************
! Closing Files and Ending the Program
!******************************************************************************************
Based on years of experience, we have developed a template for writing programs that enables users—from beginners to professionals—to write optimal code and avoid many common errors. While modular programming also aims to achieve these objectives, we believe this format is simpler and more effective.