i write a date calculator, but there always get a one-day-distance wrong

[Gucci]

<?php
/**
* check ine year is a leap year, and return the month day array
*
* @param int $year **the year must bigger than zero**
* @return array
*/
function is_leap_year($year){
$year=floor($year);
if ($year<=0) {
return false;
}
$flag = false;//leap year flag

/*
* check the year
*/
if ($year%100==0) {
if ($year%400==0) {
$flag = true;
}
}
else {
if ($year%4==0) {
$flag = true;
}
}
$mon[0] = $flag;//leap year flag
$mon[1] = 31;
$mon[2] = $flag?29:28;
$mon[3] = 31;
$mon[4] = 30;
$mon[5] = 31;
$mon[6] = 30;
$mon[7] = 31;
$mon[8] = 31;
$mon[9] = 30;
$mon[10] = 31;
$mon[11] = 30;
$mon[12] = 31;
return $mon;
}

/**
* read a datetime string and explode it in to an array
* string format: YY-M-D h:m:s
*
* @param string $datetime
* @return array
*/
function get_date_time($datetime){
$current = explode(' ', $datetime);
$date = $current[0];
$time = $current[1];
$date_tmp = explode('-',$date);
$time_tmp = explode(':',$time);
$current['year'] = $date_tmp[0]+0;
$current['month'] = $date_tmp[1]+0;
$current['day'] = $date_tmp[2]+0;
$current['hour'] = $time_tmp[0]+0;
$current['minute'] = $time_tmp[1]+0;
$current['second'] = $time_tmp[2]+0;
return $current;
}

/**
* calculate the datetime
*
*
* @param string $datetime //string format: YY-M-D h:m:s
* @param array $diff //time stamp
* array('year'=>int, 'month'=>int, 'day'=>int,
* 'hour'=>int, 'minute'=>int,'second'=>int)
* @return string //result string format: YYYY-MM-DD
hh:mm:ss
*/
function date_diff($datetime, $diff){
$current = get_date_time($datetime); //get the init time stamp
if($curent['year']<1){
return false;
}
$mon = is_leap_year($current['year']); // get the current month
days

/*
* init
*/
$second_tmp = $current['second']+$diff['second'];
$minute_tmp = $current['minute']+$diff['minute'];
$hour_tmp = $current['hour']+$diff['hour'];
$year_tmp = $current['year']+$diff['year'];
$month_tmp = $current['month']+$diff['month'];
$day_tmp=$current['day']+$diff['day'];

/*
* convert the TIME stamp into seconds
*/
$hour_tmp = $hour_tmp*60*60;
$minute_tmp = $minute_tmp*60;
$second_tmp = $hour_tmp+$minute_tmp+$second_tmp;
//convert the seconds into (day + second), the second couldn't be
negative
if ($second_tmp<0) {
$day = intval($second_tmp/(24*60*60))-1;
}
else {
$day = intval($second_tmp/(24*60*60));
}
$day_tmp=$current['day']+$diff['day']+$day;
$second_tmp = $second_tmp-($day*24*60*60);

/*
* convert the seconds into h:m:s
*/
$hour_tmp = intval($second_tmp/(60*60));
$second_tmp = $second_tmp-($hour_tmp*60*60);
$minute_tmp = intval($second_tmp/(60));
$second_tmp = $second_tmp-($minute_tmp*60);

/*
* month caculate
*/
if ($month_tmp<0) {
while ($month_tmp<1) {
$year_tmp--;
$month_tmp+=12;
}
}
else {
while ($month_tmp>12) {
$year_tmp++;
$month_tmp-=12;
}
}

/*
* day caculate
*/
if ($day_tmp<0) {
while ($day_tmp<1) {
$month_tmp--;
if ($month_tmp<1) {
$year_tmp--;
$month_tmp=12;
$mon = is_leap_year($year_tmp);
}
$day_tmp+=$mon[$month_tmp];
}
}
else {
while ($day_tmp>$mon[$month_tmp]){
$day_tmp-=$mon[$month_tmp];
$month_tmp++;
if ($month_tmp>12){
$year_tmp++;
$month_tmp=1;
$mon = is_leap_year($year_tmp);
}
}
}
if ($year_tmp<=0) { return false; }
if ($month_tmp<10) { $month_tmp='0'.$month_tmp; }
if ($day_tmp<10) { $day_tmp='0'.$day_tmp; }
if ($hour_tmp<10) { $hour_tmp='0'.$hour_tmp; }
if ($minute_tmp<10){ $minute_tmp='0'.$minute_tmp; }
if ($second_tmp<10){ $second_tmp='0'.$second_tmp; }
$str_date = $year_tmp.'-'.$month_tmp.'-'.$day_tmp.'
'.$hour_tmp.':'.$minute_tmp.':'.$second_tmp;
return $str_date;
}

/**
* Run date_diff()
**/
$diff['year'] = -10;
$diff['month'] = -100;
$diff['day'] = -500;
$diff['hour'] = -98;
$diff['minute'] = -237;
$diff['second'] = -999;
echo date_diff('2000-1-1 0:0:0',$diff)."\n";
echo date("Y-m-d H:i:s",mktime(0-98, 00-237, 0-999, 1-100, 1-500,
2000-10))."\n";
echo "\n";

$diff['year'] = 0;
$diff['month'] = 0;
$diff['day'] = -500;
$diff['hour'] = -98;
$diff['minute'] = 0;
$diff['second'] = 0;
echo date_diff('2000-1-1 0:0:0',$diff)."\n";
echo date("Y-m-d H:i:s",mktime(0-98, 00-0, 0-0, 1-0, 1-500,
2000-0))."\n";
?>

the result
=========================================
1980-04-15 17:46:21
1980-04-14 17:46:21

1998-08-14 22:00:00
1998-08-14 22:00:00

please tell me what's wrong,
thanks!

Gucci Koo

[.::[ikciu]::.]

Zebrawszy my?li Gucci <ju******@gmail.comwyklepa?:

/**
* check ine year is a leap year, and return the month day array
*
* @param int $year **the year must bigger than zero**
* @return array
*/

OMG man, you should to rewrite this code...

1. try to use date("L") for leap year
2. too much of code
3. same solution for other functions....

--
~~~~~~~~~~~~~~~~~~~~~~~~~
..::[ ikciu ]::.
gg: 718845
www: e-irsa.pl

[Paul Lautman]

This is usually because there is the North American Daylight Savings time
built in to PHP.

Why write one yourself when there are loads already written?

[Gucci]

has i have to calculate the datetime which beyond the unixtime on
32-bit server

[R. Rajesh Jeba Anbiah]

Gucci wrote:

<?php
/**
* check ine year is a leap year, and return the month day array
*
* @param int $year **the year must bigger than zero**
* @return array
*/
function is_leap_year($year){
$year=floor($year);
if ($year<=0) {
return false;
}
$flag = false;//leap year flag

/*
* check the year
*/
if ($year%100==0) {
if ($year%400==0) {
$flag = true;
}
}
else {
if ($year%4==0) {
$flag = true;
}
}
$mon[0] = $flag;//leap year flag
$mon[1] = 31;
$mon[2] = $flag?29:28;
$mon[3] = 31;
$mon[4] = 30;
$mon[5] = 31;
$mon[6] = 30;
$mon[7] = 31;
$mon[8] = 31;
$mon[9] = 30;
$mon[10] = 31;
$mon[11] = 30;
$mon[12] = 31;
return $mon;
}

<snip>

FWIW, this is one of many reasons why everyone should read K&R.

--
<?php echo 'Just another PHP saint'; ?>
Email: rrjanbiah-at-Y!com Blog: http://rajeshanbiah.blogspot.com/

[Gucci]

i solve the problem

<?php
function get_date_time($datetime){
if (!$datetime) {
return false;
}
$current = explode(' ', $datetime);
$date = $current[0];
$time = $current[1];
$date_tmp = explode('-',$date);
$time_tmp = explode(':',$time);
$current['year'] = $date_tmp[0]+0;
$current['month'] = $date_tmp[1]+0;
$current['day'] = $date_tmp[2]+0;
$current['hour'] = $time_tmp[0]+0;
$current['minute'] = $time_tmp[1]+0;
$current['second'] = $time_tmp[2]+0;
return $current;
}

function get_time_stamp($stamp_array){
if (!$stamp_array) {
return false;
}
$diff['year'] = $stamp_array[0];
$diff['month'] = $stamp_array[1];
$diff['day'] = $stamp_array[2];
$diff['hour'] = $stamp_array[3];
$diff['minute'] = $stamp_array[4];
$diff['second'] = $stamp_array[5];
return $diff;
}

function is_leap_year($year){
$year=floor($year);
if ($year<=0) {
return false;
}
$flag = false;

if ($year%100==0) {
if ($year%400==0) {$flag = true;}
}
else {
if ($year%4==0) {$flag = true;}
}
$mon = array($flag,31,($flag?29:28),31,30,31,30,31,31,30, 31,30,31);
return $mon;
}

function date_calc($stamp,&$litter,&$bigger){
$time_name=array('second','minute','hour','day','m onth','year');
$time_base=array(60,60,24,null,12,null);
$position = array_search($stamp,$time_name);

$bigger_tmp = intval($litter/$time_base[$position]);
if ($bigger_tmp<0) {
$bigger_tmp--;
}
$litter = $litter-$bigger_tmp*$time_base[$position];
$bigger+=$bigger_tmp;
}

function date_diff($start,$diff_stamp){
$current = get_date_time($start);
$diff = get_time_stamp($diff_stamp);

/*
* IMPORTANT!!!
* MAKE ALL TIMESTAMP START AT ZERO
*/
$current['year']--;
$current['month']--;
$current['day']--;

$year = $current['year']+$diff['year'];
$month = $current['month']+$diff['month'];
$day = $current['day']+$diff['day'];
$hour = $current['hour']+$diff['hour'];
$minute = $current['minute']+$diff['minute'];
$second = $current['second']+$diff['second'];

date_calc('second',$second,$minute);
date_calc('minute',$minute,$hour);
date_calc('hour',$hour,$day);
date_calc('month',$month,$year);

$year++;
$month++;
$day++;

$mon = is_leap_year($year);
if ($day<0) {
while ($day<1) {
$month--;
if ($month<1) {
$year--;
$month=12;
$mon = is_leap_year($year);
}
$day+=$mon[$month];
}
}
else {
while ($day>$mon[$month]){
$day-=$mon[$month];
$month++;
if ($month>12){
$year++;
$month=1;
$mon = is_leap_year($year);
}
}
}

if ($month<10) {$month='0'.$month;}
if ($day<10) {$day='0'.$day;}
if ($hour<10) {$hour='0'.$hour;}
if ($minute<10) {$minute='0'.$minute;}
if ($second<10) {$second='0'.$second;}
return "$year-$month-$day $hour:$minute:$second";
}
?>

[Steve]

On Sun, 27 Aug 2006 06:36:09 -0700, Gucci wrote:

if ($year%100==0) {
if ($year%400==0) {$flag = true;}

Are you *sure* this logic is correct? I'm not... and if it is, why bother
with the check for 100 years?

[Jerry Stuckle]

Steve wrote:

On Sun, 27 Aug 2006 06:36:09 -0700, Gucci wrote:

> if ($year%100==0) {
if ($year%400==0) {$flag = true;}

Are you *sure* this logic is correct? I'm not... and if it is, why bother
with the check for 100 years?

Yes, that is correct.

It is a leap year if the year is divisible by 400, or if its divisible
by 4 and not by 100.

He needs the $year % 100 for the else clause.
--
==================
Remove the "x" from my email address
Jerry Stuckle
JDS Computer Training Corp.
js*******@attglobal.net
==================