Use gregoriantojd() when you need to converts a Gregorian calendar date to a Julian day number in a PHP application. The examples below show the actual operation and its limitations.
What Is gregoriantojd() in PHP?
Converts a Gregorian calendar date to a Julian day number. The exact signature supported by your installation depends on its PHP version and enabled extensions.
Its syntax is:
gregoriantojd(int $month, int $day, int $year): intParameters and return value: The parameter types, optional arguments, references, and return type are shown in the signature above. Optional parameters are marked with an ellipsis in this reference signature.
Example 1: Basic Usage
<?php
echo gregoriantojd(1,1,2025);Result: Run the example in an environment that supports the function. Any values depending on operating-system state, installed extensions, process configuration, or network access must be checked on the target server.
Example 2: Different Input or Behavior
<?php
echo gregoriantojd(12,31,2025);Result: Run the example in an environment that supports the function. Any values depending on operating-system state, installed extensions, process configuration, or network access must be checked on the target server.
Practical Example: Applying the Function
<?php
$first = gregoriantojd(1,1,2025); $next = gregoriantojd(1,8,2025); echo $next - $first;Result: Run the example in an environment that supports the function. Any values depending on operating-system state, installed extensions, process configuration, or network access must be checked on the target server.
Important Behavior and Edge Cases
Month, day and year order matters; validate date values with checkdate().
Comparison With Related Functions
| Approach | Difference |
|---|---|
gregoriantojd() | Converts a Gregorian calendar date to a Julian day number. |
| Related operation | jdtogregorian() performs the inverse Julian-day conversion. |
Common Beginner Mistakes
| Mistake | Correct Approach |
|---|---|
| Ignoring the function-specific limitation | Month, day and year order matters; validate date values with checkdate(). |
| Confusing this function with a related operation | jdtogregorian() performs the inverse Julian-day conversion. |
Key Takeaways
- Converts a Gregorian calendar date to a Julian day number.
- Month, day and year order matters; validate date values with checkdate().
- jdtogregorian() performs the inverse Julian-day conversion.
Use gregoriantojd() for the specific operation demonstrated above. Check its prerequisites and handle failure conditions before using it with production data.