Learning Resources
String mathematical date and time functions
Date/Time Functions
• checkdate — Validate a Gregorian date
• date_add — Alias of DateTime::add
• date_create_from_format — Alias of DateTime::createFromFormat
• date_create — Alias of DateTime::__construct
• date_date_set — Alias of DateTime::setDate
• date_default_timezone_get — Gets the default timezone used by all date/time functions in a script
• date_default_timezone_set — Sets the default timezone used by all date/time functions in a script
• date_diff — Alias of DateTime::diff
• date_format — Alias of DateTime::format
• date_get_last_errors — Alias of DateTime::getLastErrors
• date_interval_create_from_date_string — Alias of DateInterval::createFromDateString
• date_interval_format — Alias of DateInterval::format
• date_isodate_set — Alias of DateTime::setISODate
• date_modify — Alias of DateTime::modify
• date_offset_get — Alias of DateTime::getOffset
• date_parse_from_format — Get info about given date formatted according to the specified format
• date_parse — Returns associative array with detailed info about given date
• date_sub — Alias of DateTime::sub
• date_sun_info — Returns an array with information about sunset/sunrise and twilight begin/end
• date_sunrise — Returns time of sunrise for a given day and location
• date_sunset — Returns time of sunset for a given day and location
• date_time_set — Alias of DateTime::setTime
• date_timestamp_get — Alias of DateTime::getTimestamp
• date_timestamp_set — Alias of DateTime::setTimestamp
• date_timezone_get — Alias of DateTime::getTimezone
• date_timezone_set — Alias of DateTime::setTimezone
• date — Format a local time/date
• getdate — Get date/time information
• gettimeofday — Get current time
• gmdate — Format a GMT/UTC date/time
• gmmktime — Get Unix timestamp for a GMT date
• gmstrftime — Format a GMT/UTC time/date according to locale settings
• idate — Format a local time/date as integer
• localtime — Get the local time
• microtime — Return current Unix timestamp with microseconds
• mktime — Get Unix timestamp for a date
• strftime — Format a local time/date according to locale settings
• strptime — Parse a time/date generated with strftime
• strtotime — Parse about any English textual datetime description into a Unix timestamp
• time — Return current Unix timestamp
• timezone_abbreviations_list — Alias of DateTimeZone::listAbbreviations
• timezone_identifiers_list — Alias of DateTimeZone::listIdentifiers
• timezone_location_get — Alias of DateTimeZone::getLocation
• timezone_name_from_abbr — Returns the timezone name from abbreviation
• timezone_name_get — Alias of DateTimeZone::getName
• timezone_offset_get — Alias of DateTimeZone::getOffset
• timezone_open — Alias of DateTimeZone::__construct
• timezone_transitions_get — Alias of DateTimeZone::getTransitions
• timezone_version_get — Gets the version of the timezonedb
Strings Functions
• addcslashes — Quote string with slashes in a C style
• addslashes — Quote string with slashes
• bin2hex — Convert binary data into hexadecimal representation
• chop — Alias of rtrim
• chr — Return a specific character
• chunk_split — Split a string into smaller chunks
• convert_cyr_string — Convert from one Cyrillic character set to another
• convert_uudecode — Decode a uuencoded string
• convert_uuencode — Uuencode a string
• count_chars — Return information about characters used in a string
• crc32 — Calculates the crc32 polynomial of a string
• crypt — One-way string hashing
• echo — Output one or more strings
• explode — Split a string by string
• fprintf — Write a formatted string to a stream
• get_html_translation_table — Returns the translation table used by htmlspecialchars and htmlentities
• hebrev — Convert logical Hebrew text to visual text
• hebrevc — Convert logical Hebrew text to visual text with newline conversion
• hex2bin — Decodes a hexadecimally encoded binary string
• html_entity_decode — Convert all HTML entities to their applicable characters
• htmlentities — Convert all applicable characters to HTML entities
• htmlspecialchars_decode — Convert special HTML entities back to characters
• htmlspecialchars — Convert special characters to HTML entities
• implode — Join array elements with a string
• join — Alias of implode
• lcfirst — Make a string's first character lowercase
• levenshtein — Calculate Levenshtein distance between two strings
• localeconv — Get numeric formatting information
• ltrim — Strip whitespace (or other characters) from the beginning of a string
• md5_file — Calculates the md5 hash of a given file
• md5 — Calculate the md5 hash of a string
• metaphone — Calculate the metaphone key of a string
• money_format — Formats a number as a currency string
• nl_langinfo — Query language and locale information
• nl2br — Inserts HTML line breaks before all newlines in a string
• number_format — Format a number with grouped thousands
• ord — Return ASCII value of character
• parse_str — Parses the string into variables
• print — Output a string
• printf — Output a formatted string
• quoted_printable_decode — Convert a quoted-printable string to an 8 bit string
• quoted_printable_encode — Convert a 8 bit string to a quoted-printable string
• quotemeta — Quote meta characters
• rtrim — Strip whitespace (or other characters) from the end of a string
• setlocale — Set locale information
• sha1_file — Calculate the sha1 hash of a file
• sha1 — Calculate the sha1 hash of a string
• similar_text — Calculate the similarity between two strings
• soundex — Calculate the soundex key of a string
• sprintf — Return a formatted string
• sscanf — Parses input from a string according to a format
• str_getcsv — Parse a CSV string into an array
• str_ireplace — Case-insensitive version of str_replace.
• str_pad — Pad a string to a certain length with another string
• str_repeat — Repeat a string
• str_replace — Replace all occurrences of the search string with the replacement string
• str_rot13 — Perform the rot13 transform on a string
• str_shuffle — Randomly shuffles a string
• str_split — Convert a string to an array
• str_word_count — Return information about words used in a string
• strcasecmp — Binary safe case-insensitive string comparison
• strchr — Alias of strstr
• strcmp — Binary safe string comparison
• strcoll — Locale based string comparison
• strcspn — Find length of initial segment not matching mask
• strip_tags — Strip HTML and PHP tags from a string
• stripcslashes — Un-quote string quoted with addcslashes
• stripos — Find the position of the first occurrence of a case-insensitive substring in a string
• stripslashes — Un-quotes a quoted string
• stristr — Case-insensitive strstr
• strlen — Get string length
• strnatcasecmp — Case insensitive string comparisons using a "natural order" algorithm
• strnatcmp — String comparisons using a "natural order" algorithm
• strncasecmp — Binary safe case-insensitive string comparison of the first n characters
• strncmp — Binary safe string comparison of the first n characters
• strpbrk — Search a string for any of a set of characters
• strpos — Find the position of the first occurrence of a substring in a string
• strrchr — Find the last occurrence of a character in a string
• strrev — Reverse a string
• strripos — Find the position of the last occurrence of a case-insensitive substring in a string
• strrpos — Find the position of the last occurrence of a substring in a string
• strspn — Finds the length of the initial segment of a string consisting entirely of characters contained within a given mask.
• strstr — Find the first occurrence of a string
• strtok — Tokenize string
• strtolower — Make a string lowercase
• strtoupper — Make a string uppercase
• strtr — Translate characters or replace substrings
• substr_compare — Binary safe comparison of two strings from an offset, up to length characters
• substr_count — Count the number of substring occurrences
• substr_replace — Replace text within a portion of a string
• substr — Return part of a string
• trim — Strip whitespace (or other characters) from the beginning and end of a string
• ucfirst — Make a string's first character uppercase
• ucwords — Uppercase the first character of each word in a string
• vfprintf — Write a formatted string to a stream
• vprintf — Output a formatted string
• vsprintf — Return a formatted string
• wordwrap — Wraps a string to a given number of characters
Math Functions
• abs — Absolute value
• acos — Arc cosine
• acosh — Inverse hyperbolic cosine
• asin — Arc sine
• asinh — Inverse hyperbolic sine
• atan2 — Arc tangent of two variables
• atan — Arc tangent
• atanh — Inverse hyperbolic tangent
• base_convert — Convert a number between arbitrary bases
• bindec — Binary to decimal
• ceil — Round fractions up
• cos — Cosine
• cosh — Hyperbolic cosine
• decbin — Decimal to binary
• dechex — Decimal to hexadecimal
• decoct — Decimal to octal
• deg2rad — Converts the number in degrees to the radian equivalent
• exp — Calculates the exponent of e
• expm1 — Returns exp(number) - 1, computed in a way that is accurate even when the value of number is close to zero
• floor — Round fractions down
• fmod — Returns the floating point remainder (modulo) of the division of the arguments
• getrandmax — Show largest possible random value
• hexdec — Hexadecimal to decimal
• hypot — Calculate the length of the hypotenuse of a right-angle triangle
• is_finite — Finds whether a value is a legal finite number
• is_infinite — Finds whether a value is infinite
• is_nan — Finds whether a value is not a number
• lcg_value — Combined linear congruential generator
• log10 — Base-10 logarithm
• log1p — Returns log(1 + number), computed in a way that is accurate even when the value of number is close to zero
• log — Natural logarithm
• max — Find highest value
• min — Find lowest value
• mt_getrandmax — Show largest possible random value
• mt_rand — Generate a better random value
• mt_srand — Seed the better random number generator
• octdec — Octal to decimal
• pi — Get value of pi
• pow — Exponential expression
• rad2deg — Converts the radian number to the equivalent number in degrees
• rand — Generate a random integer
• round — Rounds a float
• sin — Sine
• sinh — Hyperbolic sine
• sqrt — Square root
• srand — Seed the random number generator
• tan — Tangent
• tanh — Hyperbolic tangent