Counting the (year)quarters between two dates - php

Question

I have project built using laravel and a I have to build a function that counts all the complete quarters that are in the selected date range - the dates used are inserted via input.
Here are the quarters(i used numerical representations for the months)
01 - 03 first quarter
04 - 06 second quarter
07 - 09 third quarter
10 - 12 forth quarter
I would really appreciate your help,because I've been at it for an entire day now and basically have nothing to show for it,i thing I've been trying so hard i'm actually at the point where i'm so tired, i can t think straight.
I do have some code but it;s worthless, because it doesn't work, and any kind of idea or snippet of code is welcomed.
Thanks for your help in advance.

Answer 1

I managed to do this using multiple functions; basically, if this is needed for chart statistics, then a more specific approach might be the case.
I have done this in Laravel with timestamp dates as input (this code can be adapted for getting semesters also :) , it works and is already tested):
public static function getQuartersBetween($start_ts, $end_ts)
{
$quarters = [];
$months_per_year = [];
$years = self::getYearsBetween($start_ts, $end_ts);
$months = self::getMonthsBetween($start_ts, $end_ts);
foreach ($years as $year) {
foreach ($months as $month) {
if ($year->format('Y') == $month->format('Y')) {
$months_per_year[$year->format('Y')][] = $month;
}
}
}
foreach ($months_per_year as $year => $months) {
$january = new Date('01-01-' . $year);
$march = new Date('01-03-' . $year);
$april = new Date('01-04-' . $year);
$june = new Date('01-06-' . $year);
$july = new Date('01-07-' . $year);
$september = new Date('01-09-' . $year);
$october = new Date('01-10-' . $year);
$december = new Date('01-12-' . $year);
if (in_array($january, $months) && in_array($march, $months)) {
$quarter_per_year['label'] = 'T1 / ' . $year;
$quarter_per_year['start_day'] = $january->startOfMonth();
$quarter_per_year['end_day'] = $march->endOfMonth()->endOfDay();
array_push($quarters, $quarter_per_year);
}
if (in_array($april, $months) && in_array($june, $months)) {
$quarter_per_year['label'] = 'T2 / ' . $year;
$quarter_per_year['start_day'] = $april->startOfMonth();
$quarter_per_year['end_day'] = $june->endOfMonth()->endOfDay();
array_push($quarters, $quarter_per_year);
}
if (in_array($july, $months) && in_array($september, $months)) {
$quarter_per_year['label'] = 'T3 / ' . $year;
$quarter_per_year['start_day'] = $july->startOfMonth();
$quarter_per_year['end_day'] = $september->endOfMonth()->endOfDay();
array_push($quarters, $quarter_per_year);
}
if (in_array($october, $months) && in_array($december, $months)) {
$quarter_per_year['label'] = 'T4 / ' . $year;
$quarter_per_year['start_day'] = $october->startOfMonth();
$quarter_per_year['end_day'] = $december->endOfMonth()->endOfDay();
array_push($quarters, $quarter_per_year);
}
}
return $quarters;
}
and getting the years between:
public static function getYearsBetween($start_ts, $end_ts, $full_period = false)
{
$return_data = [];
$current = mktime(0, 0, 0, date('m', $start_ts), date('d', $start_ts), date('Y', $start_ts));
while ($current < $end_ts) {
$temp_date = $current;
$year = new Date($temp_date);
$return_data[] = $year;
$current = strtotime("+1 year", $current); // add a year
}
if ($full_period) {
$return_data[] = $end_ts;
}
return $return_data;
}
, also getting the months needed
public static function getMonthsBetween($start_ts, $end_ts, $full_period = false)
{
$return_data = $month_list = [];
$current = mktime(0, 0, 0, date('m', $start_ts), date('d', $start_ts), date('Y', $start_ts));
while ($current <= $end_ts) {
$temp_date = $current;
$date = new Date($temp_date);
$month_list[] = $date;
$current = strtotime("+1 month", $current); // add a month
}
$start_date_last_month = new Date(array_first($month_list));
$start_date_last_month = $start_date_last_month->startOfMonth()->format('m-d');
$temp_end_date = new Date($start_ts);
$temp_end_date = $temp_end_date->format('m-d');
if ($start_date_last_month < $temp_end_date) {
array_shift($month_list);
}
$end_date_last_month = new Date(end($month_list));
$current_day_month = $end_date_last_month->endOfMonth()->format('m-d');
$temp_end_date = new Date($end_ts);
$end_day_of_month = $temp_end_date->format('m-d');
if ($end_day_of_month < $current_day_month) {
array_pop($month_list);
}
if (count($month_list) == 0) {
$month_list[] = $end_date_last_month->subMonth();
}
$return_data = $month_list;
if ($full_period) {
$return_data[] = $end_ts;
}
return $return_data;
}

Answer 2

You can do something like in this example:
$February = 2;
$October = 10;
$completedQuarters = ceil($October/3) - ceil($February/3); // = 3
What about the quarter in which the date range starts, should it also count? If it should only count if it begins in the first month of a quarter you can check for it like this:
$completedQuarters = ceil($October/3) - ceil($February/3) -1; // = 2
if($February-1%3 == 0) $completedQuarters += 1;
You´re description is not very clear, let me know if that´s what you had in mind.

Answer 3

Not sure if the following is what you are meaning but might be useful
$date_start='2015/03/12';
$date_end='2017/11/14';
$timezone=new DateTimeZone('Europe/London');
$start=new DateTime( $date_start, $timezone );
$end=new DateTime( $date_end, $timezone );
$difference = $end->diff( $start );
$months = ( ( $difference->format('%y') * 12 ) + $difference->format('%m') );
$quarters = intval( $months / 3 );
printf( 'Quarters between %s and %s is %d covering %d months', $start->format('l, jS F Y'), $end->format('l, jS F Y'), $quarters, $months );
/*
This will output
----------------
Quarters between Thursday, 12th March 2015 and Tuesday, 14th November 2017 is 10 covering 32 months
*/

Answer 4

Something like this in the function and you should be set.
use Carbon\Carbon;
$first = Carbon::parse('2012-1-1'); //first param
$second = Carbon::parse('2014-9-15'); //second param
$fY = $first->year; //2012
$fQ = $first->quarter; //1
$sY = $second->year; //2014
$sQ = $second->quarter; //3
$n = 0; //the number of quarters we have counted
$i = 0; //an iterator we will use to determine if we are in the first year
for ($y=$fY; $y < $sY; $y++, $i++) { //for each year less than the second year (if any)
$s = ($i > 0) ? 1 : $fQ; //determine the starting quarter
for ($q=$s; $q <= 4; $q++) { //for each quarter
$n++; //count it
}
}
if ($sY > $fY) { //if both dates are not in the same year
$n = $n + $sQ; //total is the number of quarters we've counted plus the second quarter value
} else {
for ($q=$fQ; $q <= $sQ; $q++) { //for each quarter between the first quarter and second
$n++; //count it
}
}
print $n; //the value to return (11)