Solved: Date comparison to same 'wednesday' of previous year

Going forward, you might want to think about leaving these questions open a little longer. There is a perfectly suitable solution to the one-year-ago problem. But that said, day-by-day sales reports are almost always too granular to be useful. What if it snowed on one of the days but was sunny and nice on the other? The potential for wide and uncontrolled short-term variability make month-over-month and quarter-over-quarter statistics, generally, more meaningful.

Bookmark these articles for future reference.

Procedural
https://www.experts-exchange.com/articles/201/Handling-Date-and-Time-in-PHP-and-MySQL-Procedural-Version.html

OOP
https://www.experts-exchange.com/articles/20920/Handling-Time-and-Date-in-PHP-and-MySQL-OOP-Version.html

See if this little function works the way you want.

<?php // demo/temp_tjyoung.php
/**
 * https://www.experts-exchange.com/questions/29012870/Date-comparison-to-same-'wednesday'-of-previous-year.html
 */
error_reporting(E_ALL);
echo '<pre>';


function yearAgoWeekDay($today = 'Today', $format = 'Y-m-d D')
{
    $day = date('l', strtotime($today));
    $ago = date('Y-m-d', strtotime("$today - 1 YEAR - 3 DAYS"));
    $ago = date($format, strtotime("$ago NEXT $day"));

    return $ago;
}


// TEST THE FUNCTION
$arr = date_range('December 1, 2015', 'March 15, 2017', 'Y-m-d D');
foreach ($arr as $my_date)
{
    echo PHP_EOL . $my_date . " Year Ago Weekday: " . yearAgoWeekDay($my_date);
}


// UNRELATED FUNCTION TO GET A range() ARRAY OF DATES
function date_range($a, $z, $format='Y-m-d')
{
    $return = [];
    $interval_p1d = new DateInterval('P1D');

    // NORMALIZE THE DATES (MAYBE USE TRY/CATCH SANITY CHECKS?)
    $alpha   = new DateTime($a);
    $omega   = new DateTime($z);

    // CREATE THE RANGE
    while ($alpha <= $omega) {
        $return[] = $alpha->format($format);
        $alpha->add($interval_p1d);
    }
    return $return;
}

Open in new window