Acknowledgments This post continues my exploration of concepts and techniques related to both the way so-called “Jewish times” (zmanim) are calculated; as well as the techniques needed to use the – a library of functions that let you easily calculate Jewish times. PHP Zmanim library Once again, I owe a huge debt of gratitude to several folks – including Eliyahu Hershfeld, creator of the , Zachary Weixelbaum (owner of the PHP Zmanim library, a port of Kosher Java), Elyahu Jacobi (who built with those tools and patiently explained so many concepts to me), and Maor Neim, who offered explanations that turned theory into practice. Kosher Java library RoyZmanim.com Introduction , I explored both the foundational concepts of Jewish time calculations (zmanim) and also the initial steps needed to install and use PHP Zmanim. We got as far as calculating sunrise with that library. In my last post By itself, this isn’t particularly impressive. The fact is that with the same information (latitude, longitude, time zone, and a specific date) you can get the same information using PHP’s built-in functions. In this post, we’re going to get into the types of calculations you CAN’T get with built-in PHP tools, not only because they require some “interesting” time manipulations, but because there are so many ways to calculate the same religiously significant moment, based on various Rabbinic opinions and traditions. The Answer to Every Jewish Question Starts With “Well, It Depends…” Let me take a minute to unpack that idea in a little more detail. In the last post, I started to get into this idea: Dawn is the moment when light (but not the sun) is visible over the horizon. Unfortunately, whether or not there is or isn’t “light” is highly subjective, and therefore the way it’s come to be calculated ranges all over the map. Some traditions use a fixed number of clock minutes before sunrise or after sunset. Others will use astronomy to identify the time when the sun is below the horizon by a specific number of degrees. Others will use a formula, such as taking the amount of daylight (from sunrise to sunset), dividing that into 10 equal parts, and then subtracting that amount from sunrise or adding it to sunset. Still others will take the time the sun is below the horizon on an “equal” day (meaning the spring or fall equinox, when the amount of sunshine and darkness are exactly the same), calculate the difference (in clock minutes) between that time and sunrise, normalize those minutes against “seasonal minutes” (“sha’ot zmaniyot”) for the specific day in question, and finally subtract that amount from sunrise (or add THAT to sunset) for the day in question. One moment of the day, but a wide variety of ways to determine it. It may be hard for those outside of mainstream orthodox Judaism to understand and is definitely the subject of a completely different type of blog post, but the answer is to embrace the understanding that all of the calculations above (and many others) are capital-T “True.” Not just in a “well, it’s how I feel about it so it’s true to me” kind of way, but as being absolutely, factually, empirically true even when one method stands in opposition to another (or several others). Like I said, THAT is the topic of a completely different blog post. For now, I mention this to explain why, in creating the , Eliyahu Hershfeld took the route of enabling the ability to easily calculate times using ANY of those methods, rather than trying to espouse a single method and coding exclusively for that. Kosher Java library And ports – such as Zachary Weixelbaum’s – simply continue with that ideal. PHP Zmanim library Which brings us back to the nitty-gritty of using the PHP Zmanim library. Making Time Pretty , we left off with this snippet of code: In the last post <?php
require 'vendor/autoload.php';
use PhpZmanim\Zmanim;
use PhpZmanim\Calendar\ComplexZmanimCalendar;
use PhpZmanim\Geo\GeoLocation;


# Set variables:
#41.4939407, -81.516709;
$locname = "Beit Knesset Chochmat Shlomo, Beachwood, OH";
$lat = 41.4939407;
$long = -81.516709;
$elev = 0;
$tz = 'America/New_York';

$getyear = 2024;
$getday = 20;
$getmonth = 12;
$testzmanim = Zmanim::create($getyear, $getmonth, $getday, $locname, $lat, $long, $elev, $tz);
$sunrise = $testzmanim->sunrise;
echo "$sunrise\n";
?> Which produced a result that looked something like this: 2024-12-20 07:48:52 It works, but it’s not what I’d want to see on a page when I’m just expecting a simple “7:48 am”. Which brings me to the next interesting insight for the PHP Zmanim library: You can format the output using another function, rather than hammering through PHP’s built-in options. You’ll still use the but getting what you want is easier. PHP time/date formatting codes Let’s say I want to only display the hour, minute, and am/pm for the sunrise output. I’d add a line like this: $sunrise = $zmanim->sunrise;
$sunrise = $sunrise->format('g:i a'); Which would look like this when printed on the screen: 7:48 am Getting Your First Actual real-time – Mincha Gedola The problem with using sunrise/sunset as an example is that PHP has built-in options to do the exact same thing. So, let’s look at getting a time that is more relevant to Jewish religious times: the earliest time for afternoon prayers (Mincha Gedola). Once again, it’s somewhat anti-climactic in that it’s a single command: $gedolah = $zmanim->minchaGedola; Which outputs a time like this: 2024-12-20 12:46:55 HOWEVER, as I mentioned earlier in this post, there are several ways to calculate this time. Here are all the methods supported by the PHP Zmanim library: minchaGedola: Returns a time of 6.5 halachic hours (shaos zmaniyos) after sunrise. minchaGedola30Minutes: Returns the time 30 standard (clock) minutes after the half-day calculation (chatzot). minchaGedola72Minutes: Calculates according to the Magen Avraham (Abraham Abele Gombiner, 1635-1682) with the day starting 72 minutes before sunrise and ending 72 minutes after sunset. minchaGedola16Point1Degrees: Calculated according to the Magen Avraham with the day starting and ending when the sun is 16.1 degrees below the horizon. minchaGedolaAhavatShalom: Calculated based on the opinion of as half a seasonal hour (shaah) after mid-day (chatzos) with seasonal minutes (shaos zmaniyos) calculated based on a day starting 72 minutes before sunrise and ending 13.5 minutes after sunset. Rabbi Yaakov Moshe Hillel minchaGedolaGreaterThan30: This is a convenience method that returns the later of the standard “minchaGedola” function or ‘minchaGedola30Minutes. In the winter when 1/2 of a seasonal hour (sha’ah) is less than 30 minutes, then minchaGedola30Minutes will be returned, otherwise, the regular minchaGedola will be returned. minchaGedolaAteretTorah: This method returns the time of according to the Magen Avraham with the day starting and ending when the sun is 16.1 degrees below the horizon. mincha ketana minchaGedolaBaalHatanya: This calculation is based on the opinion of the . Baal Hatanya minchaGedolaBaalHatanyaGreaterThan30: This is a convenience method that returns the later of either minchaGedolaBaalHatanya or minchaGedola30Minutes. In the winter when 1/2 of a seasonal hour (sha’ah) is less than 30 minutes, then minchaGedola30Minutes will be returned, otherwise minchaGedolaBaalHatanya will be returned. minchaGedolaGRAFixedLocalChatzos30Minutes: This method returns a time based on opinion. Rav Moshe Feinstein’s As you can see, there are a number of opinions. Determining which one you want/need to use is outside the scope of this blog post and will likely require some conversations with the users of the app or website, as well as a Rabbi. Or two. Or several. But the good news is that to use any of them, it’s as simple as: $gedolah = $zmanim->minchaGedola16Point1Degrees;
$gedolah = $gedolah->format('g:i a'); Getting Something Complicated – Nightfall (Tzais Hakochavim) Now that you’ve seen how we get one time, you should understand that even times that my previous post labeled as “complicated” aren’t that complicated. Furthermore, it should reinforce your understanding of just how powerful a tool like PHP Zmanim is because of what it enables you to do in such a short time. Calculating nightfall (tzais hakochavim) is as simple as the command $tzais = $zmanim->tzais; If there is any challenge at all, it’s the sheer number of variations to consider. I’m listing them here without explanation, just so you have a sense of how many there are. That’s right, there are 32 different options for calculating this one time. I list them here without detailed explanation simply to underscore my point: tzais tzais72 tzaisGeonim3Point7Degrees tzaisGeonim3Point8Degrees tzaisGeonim5Point95Degrees tzaisGeonim3Point65Degrees tzaisGeonim3Point676Degrees tzaisGeonim4Point61Degrees tzaisGeonim4Point37Degrees tzaisGeonim5Point88Degrees tzaisGeonim4Point8Degrees tzaisGeonim6Point45Degrees tzaisGeonim7Point083Degrees tzaisGeonim7Point67Degrees tzaisGeonim8Point5Degrees tzaisGeonim9Point3Degrees tzaisGeonim9Point75Degrees tzais60 tzaisAteretTorah tzais72Zmanis tzais90Zmanis tzais96Zmanis tzais90 tzais120 tzais120Zmanis tzais16Point1Degrees tzais26Degrees tzais18Degrees tzais19Point8Degrees tzais96 tzaisBaalHatanya tzais50 Time (and This Blog Series) Marches On Armed with the information in this post, you could probably make decent headway simply by looking through the main README on Zachary’s page itself, and selecting the best (for your purposes) calculations for: PHP Zmanim Sunrise and Sunset (no, do not sing ) That Song A “seasonal” hour (Sha’ah Zmanim) Dawn (alos hashachar) The earliest time to put on tallit and tefillin (misheyakir) The latest time to say Shema (sof zman kria shema) The latest time for morning prayers (sof zman tefillah) When Passover begins Halfway through the day (chatzos) The earliest time for afternoon prayers (mincha gedola) The “best” time for afternoon prayers (mincha ketana) The latest time for afternoon prayers (plag hamincha) The time to light Shabbat candles Dusk – the time between sunset and night (bain hashmashot) Night (tzais hakochavim) Halfway through the night (chatozs halayla) But there is still more to cover. In upcoming articles, I’ll talk about: Taking these standard times and adjusting them for synagogue specific needs (“Mincha starts 25 minutes before Shkia each day”). Using the PHP Zmanim library to display non-time calculations such as the weekly Torah Portion, Rosh Chodesh, and the Molad. Leveraging the build-in astronomy functions for time calculations that aren’t built into the library itself. I hope you’ll continue on this journey with me. As always if you have questions, comments, or kudos, please leave them in the comments.

What Daylight Are We Saving? Time Data Series

Job Listed As In-Office? You Might Be Able To Go Remote

Read My Stories

Portfolio

Newsletter

Buy My Book

Buy Me a Coffee

Principal Technical Evangelist

Principal Developer Relations Advocate

Head Geek

Too Long; Didn't Read

Time Data Series: How to Work With PHP Zmanim

Time Data Series: How to Work With PHP Zmanim

About Author

Comments

TOPICS

THIS ARTICLE WAS FEATURED IN

Related Stories

ACTING (like we care about) Securityms: Focusing on Risks, Outcomes, and Business Value

Time Data Series: A Beginner's Guide to PHP Zmanim

Time Data Series: It's Not About What You Said - It's More About How You Said It

How to Implement PHP Zmanim in WordPress Using Zmanim-WP

Religion In The Workplace?

What Daylight Are We Saving? Time Data Series

ACTING (like we care about) Securityms: Focusing on Risks, Outcomes, and Business Value

Time Data Series: A Beginner's Guide to PHP Zmanim

Time Data Series: It's Not About What You Said - It's More About How You Said It

How to Implement PHP Zmanim in WordPress Using Zmanim-WP

Religion In The Workplace?

What Daylight Are We Saving? Time Data Series

Light-Mode

Classic

Newspaper

Minty

Dark-Mode

Neon Noir

Minty

HN StartUps