First Tuesday PHP

Question

The first_tuesday() function should return the date of the first Tuesday of year, but especially in the case of 2011 it returns a wrong value. how to Fix the code so it works in all cases

function first_tuesday($year){

    $first_january = mktime(0,0,0,1,1,$year);
    $day_week = date("w",$first_january );
    $first_tuesday = $first_jan + ((2 - $day_week) % 7)* 86400;
    return date("d/m/Y",$first_tuesday);
}

Can you write the variable names in English so it's easier for us to understand what you're trying to do? — Amal Murali, Jan 08 '14 at 08:02
Please remember to accept an answer by clicking on a check mark beside one of the answers if you have found a solution to your problem here. — rink.attendant.6, Jan 08 '14 at 08:24

xdazz · Answer 1 · 2014-01-08T08:12:39.233

5

strtotime is clever enough to get what you want:

function first_tuesday($year){
  return date('d/m/Y', strtotime("first Tuesday of January $year"));
}

edited Jan 08 '14 at 08:12

answered Jan 08 '14 at 08:05

xdazz

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No it's not. On my machine (PHP 5.5.3) your code returns "07/01/2014" – Victor Stanciu Jan 08 '14 at 08:07
No, this is not correct. Your function will return `07/01/2014` -- but the actual value is `04/01/2011`. – Amal Murali Jan 08 '14 at 08:09
1

07/01/2014 is correct though? For the year 2014. – MattP Jan 08 '14 at 08:09
@AmalMurali What do you mean ? – xdazz Jan 08 '14 at 08:11
It returns `07/01/2014` no matter which year you input. For 2011 it should return `04/01/2011` – Victor Stanciu Jan 08 '14 at 08:11
@AmalMurali, Am confused :P , dazz is right. Maybe you are saying it for the year 2011. – Shankar Narayana Damodaran Jan 08 '14 at 08:11
@ShankarDamodaran: The results returned by this function are incorrect. See here: https://eval.in/87071 – Amal Murali Jan 08 '14 at 08:13
@ShankarDamodaran no, he is not. His function returns the exact same result no matter what year you input into it. It should return the first Tuesday of the `$year` you give it, not the first Tuesday of 2014. – Victor Stanciu Jan 08 '14 at 08:13
@AmalMurali Oh, you are right. Can't miss the `January`(month part). – xdazz Jan 08 '14 at 08:13
Yep, including the month works. – Victor Stanciu Jan 08 '14 at 08:14
1

@AmalMurali, Amazing!! Let me buy you a cup of tea ! :) – Shankar Narayana Damodaran Jan 08 '14 at 08:15
@xdazz: Didn't notice your edit. -1 changed to +1 ;) – Amal Murali Jan 08 '14 at 08:19

Amal Murali · Accepted Answer · 2014-01-08T08:17:52.883

4

Use DateTime class instead:

function first_tuesday($year){
    $day = new DateTime(sprintf("First Tuesday of January %s", $year));
    return $day->format('d/m/Y');
}

Usage:

echo first_tuesday(2011);

Output:

04/01/2011

edited Jan 08 '14 at 08:17

answered Jan 08 '14 at 08:11

Amal Murali

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You probably meant `return` instead of `echo` in your function. :) – rink.attendant.6 Jan 08 '14 at 08:17
@rink.attendant.6: Right. Fixed it, thanks! – Amal Murali Jan 08 '14 at 08:17
by the way check this code $exclus=array(1,4); function hasard(){ $resultat=rand(1,10); return $resultat; } echo "Nombre au hasard : ".hasard()."\n"; – user3172273 Jan 08 '14 at 08:20
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@user3172273: That's a different question. Please post it as such. Click on the [Ask question](http://stackoverflow.com/questions/ask) button. Make sure you include ALL the relevant details, and include the expected output in your question. Also, most of the users on this site don't speak , so I suggest you post the question (and code) in English. Cheers! – Amal Murali Jan 08 '14 at 08:23

rink.attendant.6 · Answer 3 · 2014-01-08T08:12:16.797

This seems to work for me:

<?php

$first_tuesday = new DateTime("first Tuesday of January 2011");
echo $first_tuesday->format('Y-m-d H:i:s');

?>

Putting it into functional form:

<?php

/**
 * @return DateTime Returns a DateTime object representing the
 *                  first Tuesday of the year
 */
function first_tuesday($year){
    $first_tuesday = new DateTime("first Tuesday of January $year");
    return $first_tuesday;
}

?>

If you just want the string in your format, then:

<?php

/**
 * @return DateTime Returns a string representing the first
 *                  Tuesday of the year in the d/m/Y format
 */
function first_tuesday($year){
    $first_tuesday = new DateTime("first Tuesday of January $year");
    return $first_tuesday->format('d/m/Y');
}

?>

You can read more about the DateTime class in the PHP manual (which is also available in French, as that seems to be your native language based on the original question.)

score 0 · Answer 4 · answered Jan 08 '14 at 08:08

0

$start_of_year = strtotime("01.01.2011");
$first_tuesday = strtotime("tuesday", $start_of_year);

echo date('d.m.Y', $first_tuesday); // 04.01.2011

answered Jan 08 '14 at 08:08

Victor Stanciu

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score 0 · Answer 5 · answered Jan 08 '14 at 08:12

0

Simple:

function first_tuesday($year)
{
    return date("d/m/Y",strtotime('first Tuesday january '.$year));
}

No need to use Objects, this is the fastest way of getting it.

answered Jan 08 '14 at 08:12

Ervin

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wow great,, that works perf – user3172273 Jan 08 '14 at 08:14
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`Fastest` -- Irrelevant. You use DateTime not because it's fast, but because it's *better*. – Amal Murali Jan 08 '14 at 08:14

First Tuesday PHP

5 Answers5