Fortran Date/Time Utilities

A comprehensive Fortran module for handling date and time operations with robust error handling and formatting capabilities.

Features

• Display current date, time, and day of week
• Show timezone information
• Calculate days left in the current year
• Leap year detection
• Error handling for invalid dates
• Properly formatted output
• Time difference calculations

Project Structure

fortran-datetime-utils/
├── .vscode/
│   └── tasks.json          # VS Code build tasks
├── src/
│   ├── DateUtils.f90       # Date utilities module
│   └── DateTimeUtils.f90   # Date and time utilities module
├── compile.bat             # Windows build script
├── compile.sh              # Linux/macOS build script
├── Packing.f90             # Main program example
└── README.md               # This file

Getting Started

Prerequisites

• A Fortran compiler (gfortran 8.0+ recommended)
• Optional: Visual Studio Code with the Modern Fortran extension

Building and Running

This project can be built using VS Code with the provided tasks, or manually using gfortran:

Using VS Code

1. Open the project folder in VS Code
2. Press Ctrl+Shift+B to build and run the program
3. To clean the build, select the "Clean Build" task from the Command Palette

Manual build (Windows)

# Run the build script
compile.bat

Manual build (Linux/macOS)

# Make the build script executable
chmod +x ./compile.sh

# Run the build script
./compile.sh

Manual compilation (any platform)

# Create module directory
mkdir -p build/mod

# Compile modules
gfortran -c -Jbuild/mod -Ibuild/mod -Wall -O3 src/DateUtils.f90
gfortran -c -Jbuild/mod -Ibuild/mod -Wall -O3 src/DateTimeUtils.f90

# Compile main program
gfortran -Ibuild/mod -Wall -O3 -o build/Packing src/DateUtils.f90 src/DateTimeUtils.f90 Packing.f90

# Run the program
./build/Packing  # Linux/macOS
build\Packing    # Windows

Usage

Basic example

program DateTimeExample
    use DateUtils
    use DateTimeUtils
    implicit none
    
    type(DateTime) :: currentDateTime
    integer :: status
    
    ! Get current date and time
    status = GetDateTime(currentDateTime)
    
    if (status == 0) then
        ! Format and display date information
        print *, 'Current date: ', FormatDate(currentDateTime%year, currentDateTime%month, currentDateTime%day)
        print *, 'Day of week: ', trim(currentDateTime%dayOfWeek)
    end if
end program DateTimeExample

Advanced usage

See the included Packing.f90 for a more comprehensive example that demonstrates additional features like time zone information and calculating days left in the year.

Key Components

DateUtils Module

The DateUtils module provides core date functionality:

• Day of week calculation
• Leap year detection
• Date validation
• Date formatting

DateTimeUtils Module

The DateTimeUtils module builds on DateUtils to provide:

• DateTime type definition
• Current date/time retrieval
• Time formatting
• Timezone information
• Time difference calculations

License

This project is licensed under the MIT License - see the LICENSE file for details.

Author

Created by Artem
February 2025