PHP Calendar Functions Complete Reference Last Updated : 24 Jan, 2023 Comments Improve Suggest changes Like Article Like Report The calendar extension contains a series of functions to represent the calendar date into a different format. The standard date is based on Julian Day Count. The date count starting from January 1st, 4713 B.C. is known as Julian Day Count. First, the date is converted into Julian Day Count and then converted into a calendar system. Example: The program below illustrate the use of jdtofrench() function. PHP <?php // PHP program to demonstrate the // use of jdtofrench() function // converts date to julian integer $jd = frenchtojd(1, 7, 13); // prints the julian day integer echo "The julian day integer is ", $jd, "\n"; // converts the Julian day to French date $date = jdtofrench($jd); // prints the date echo "The french date initially taken was ", ($date), "\n"; ?> Output: The julian day integer is 2380229 The french date initially taken was 1/7/13 The complete list of calendar functions are given below: PHP Calendar FunctionsDescriptioncal_days_in_month()Return the number of days in a month for a specific year. cal_from_jd()Returns the array containing calendar information of the specified calendar.cal_info()Return information about a specified calendar. cal_to_jd()Convert a specified date into Julian Day Count. easter_date()Returns the Easter date in the year passed as an argument. easter_days()Returns the number of days after March 21, that the Easter Day is in the given yearfrenchtojd()Convert the date in the French republican calendar and converts it to a Julian Day count.gregoriantojd()Converts a Gregorian date to a Julian Day Count. jddayofweek()Returns the given day of the week of a Julian integer passed in the argument.jdmonthname()Returns the month name of a Julian day number passed as the argument. jdtofrench()Converts a Julian Day Integer to a French date. jdtogregorian()Converts a Julian Day Integer to a Gregorian date.jdtojulian()Convert a Julian day count to a Julian calendar date.jdtounix()Convert a Julian day date into a Unix Timestamp. jewishtojd()Converts a Jewish Date to a Julian Day Count.juliantojd()Convert Julian calendar Date to Julian Day countunixtojd()Converts the Unix timestamp to Julian Day count. Comment More infoAdvertise with us Next Article PHP Calendar Functions Complete Reference D dharmendra_kumar Follow Improve Article Tags : Web Technologies PHP PHP-date-time Similar Reads PHP intl Functions Complete Reference The Complete list of PHP intl Functions are listed below: Collator PHP collator_asort() FunctionPHP collator_compare() FunctionPHP Collator __construct() FunctionPHP Collator create() FunctionPHP collator_sort_with_sort_keys() FunctionPHP collator_sort() Function IntlCalendar PHP IntlCalendar add() 1 min read PHP Math Functions Complete Reference The predefined math functions in PHP are used to handle the mathematical operations within the integer and float types. These math functions are part of the PHP core. Installation: These functions have not required any installation. The complete list of PHP math functions are given below:Example: Pr 3 min read PHP String Functions Complete Reference Strings are a collection of characters. For example, 'G' is the character and 'GeeksforGeeks' is the string. Installation: These functions are not required any installation. These are the part of PHP core. The complete list of PHP string functions are given below: Example: This program helps us to c 6 min read PHP Filesystem Functions Complete Reference The Filesystem function is used to access and manipulate filesystem. It is the part of PHP code so no need to install these functions. For accessing the files on the system, the file path will be used. On Unix system, forward slash (/) is used as a directory separator and on Windows platform, both f 4 min read JavaScript Function Complete Reference A JavaScript function is a set of statements that takes inputs, performs specific computations, and produces outputs. Essentially, a function performs tasks or computations and then returns the result to the user.Syntax:function functionName(Parameter1, Parameter2, ..) { // Function body}Example: Be 3 min read Like