PHP | cal_to_jd() Function

The cal_to_jd() function is an inbuilt function in PHP which is used to converts a specified date into Julian Day Count. The cal_to_jd() function calculates the Julian day count for a date in the specified calendar. This function supports CAL_GREGORIAN, CAL_JULIAN, CAL_JEWISH and CAL_FRENCH calendars.
Syntax:

int cal_to_jd( $calendar, $month, $day, $year )

Parameters: This function accepts four parameters as mentioned above and described below:  

• $calendar: It is used to specify the calendar for calculation. The calendar values are Gregorian calendar, French calendar, Jewish calendar and Julian calendar.
• $month: It is used to specify the Month in the selected calendar.
• $day: It is used to specify the Day in the selected calendar.
• $year : It is used to specify the year in the selected calendar.

Return Value: This function returns a Julian Day number.
Below programs illustrate the cal_to_jd() function in PHP.
Program 1:

php

<?php

// Converts a Gregorian calendar Date
// into Julian Day number.
$date = cal_to_jd(CAL_GREGORIAN, 11, 03, 2007);

// Prints the conversion of date to
// Julian Day number.
echo $date;
?>

Output:

2454408

Program 2:

php

<?php

// Converts Julian calendar Date into
// Julian Day count.
$date = cal_to_jd(CAL_JULIAN, 7, 20, 20017);

// Prints the above conversion.
echo $date;
?>

Output:

9032468

Reference: http://php.net/manual/en/function.cal-to-jd.php