0:00 what does a mathematicians parrot say
0:04 ah a polynomial hey everybody
0:13 Joakim in here and in this video we are
0:15 gonna be going over the basics of pi
0:17 right so we're gonna be going over about
0:20 a few of the demos some of the more
0:22 simpler demos that you saw on the PI
0:24 product page so without further ado
0:26 let's jump on in and check it out so
0:29 here we are inside the pi demo project
0:32 that ships with the pi stack and what
0:34 this in this first part of the video
0:35 we're gonna be reviewing a demos 1 2 & 3
0:39 okay now before i'd start jumping into
0:42 settings and show you how to set
0:43 everything up well let's go just go
0:45 ahead and preview and see exactly what
0:47 these demos do for us so we see in this
0:50 first demo we're taking the number of
0:52 pixels in this number field and we're
0:54 converting them to REM essentially we're
0:56 just dividing it by 16 right so here we
1:00 have if it's 16 pixels we have one REM
1:02 and if we increase that value we'll see
1:04 that PI automatically converts the
1:07 numbers that we want into REM and if
1:09 you've ever used foundation before
1:11 you've probably recognize the REM unit
1:13 it's a responsive sizing unit that is
1:15 used all throughout foundation so this
1:18 is a great little simple demo that
1:20 converts pixels into REM values this
1:24 next demo takes a value from a slider
1:27 okay and as you see as I scroll here all
1:30 the values here will change so this
1:33 first one basically takes the value of
1:35 the slider and multiplies by 3 and then
1:38 the rest of the values here are
1:39 basically rounded versions of that
1:42 number so we have rounding it the
1:44 ceiling floor will dive into what all
1:46 these different values give us but it's
1:48 just great to know that we can derive
1:50 different number of values based off a
1:52 slider as well
1:53 the third demo that we're going to be
1:55 looking at in the first part of this
1:57 video is demo 3 and this is a simple way
2:00 of defining a radius of a circle and
2:02 here we find the perimeter and the area
2:05 of a circle and we see the the actual
2:08 formulas that we use over here so this
2:11 common mathematical you know geometry
2:13 where we can find the perimeter and
2:15 areas of a circle
2:17 just by defining a radius I just want to
2:20 take a quick break out here something I
2:23 should have mentioned is that in this
2:25 demo we're gonna be using all foundation
2:28 form stacks now pi doesn't require a
2:31 foundation it will work with any form
2:33 stack out there at least it should right
2:36 we tested it with forms plus and with
2:38 form snap works a treat okay but for
2:42 this demo we're gonna be using
2:43 foundation forms now pi doesn't ship
2:46 with its own forms at all it you have to
2:48 use it with an existing form solution
2:50 right so all throughout these demos
2:53 we're going to be using the foundation
2:56 forms so if you're familiar with those
2:59 great if not you can use your favorite
3:02 form stack and PI should work
3:04 identically um just with your favorite
3:07 form stack so let's jump back in and
3:09 finish these demos and I hope you enjoy
3:12 pi okay now throughout the PI demo
3:15 you'll notice that one thing we've done
3:18 is we've added a pen stack into the demo
3:21 and this is a free stack that I released
3:23 last year and it's a great way of just
3:25 adding notes for you in edit mode so if
3:28 you don't have this stack go to my
3:30 website download it for free and it's
3:32 just a great way of displaying notes and
3:35 we added notes for every single demo
3:37 that kind of explains about that demo
3:41 and some unique things about it so if
3:44 you're perusing through the demo file
3:45 this pen stack is a great way of seeing
3:48 notes and things about the particular
3:51 demo that you're looking at so one first
3:54 thing we'll notice with PI is that I
3:55 have it inside of a form stack now you
3:59 don't need to have pi inside of a form
4:01 however in this particular demo here or
4:05 this page I have a lot a lot of Pi
4:08 instances right so it is pi is a lot
4:12 more performant when you have it inside
4:15 of a form stack reason being is pi
4:18 watches for various changes in elements
4:23 within the page now if you have it
4:26 within a form it only watches the form
4:29 elements within that
4:31 however if you have pie outside of a
4:34 forum it will look for instances on the
4:37 entire page so just be careful if you
4:40 want to have pie lots of pies on a page
4:43 and maybe that have different formulas
4:45 that do different things you might want
4:47 to encapsulate them inside of a single
4:49 form stack now if we look at this form
4:52 stack this is a foundation form you'll
4:54 notice that I turned off everything
4:55 right I have no validation noce emails
4:58 no my sequel it's just a form that does
5:00 essentially nothing right but it's a
5:03 great way of encapsulating pie so that
5:06 you know we don't need it's faster and
5:09 works a little bit better
5:12 so next up we have let's look at the
5:14 details of this demo here we have a
5:17 single number input so this is just a
5:19 normal number input and if we notice I
5:22 give it a field name of pixels okay
5:24 because that's exactly what this does
5:26 right it gives us the pixels that we
5:28 want
5:30 and here's the pie okay so we added pie
5:33 to the page and what we've done here is
5:36 this is in this area here this is where
5:38 you type in your formula so this is what
5:42 I want pie to do and hopefully it's
5:45 pretty self-explanatory if we look at
5:48 the syntax here you'll notice that we're
5:50 using a common kind of mustache syntax
5:52 that you've probably familiar with if
5:54 you used foundation forms or a lot of my
5:56 other stacks use two curly braces and
6:00 then the name of the field that we want
6:03 so if we remember here I in this first
6:05 number stack I gave it a name of pixels
6:08 so here I'm gonna put that pixels name
6:11 inside brackets and pie is gonna take
6:14 the value from that field and insert it
6:16 into my formula then simply I do divided
6:20 by 16 and we're done now Pi will then
6:24 take the value from the number and
6:26 divide it by 16
6:29 now here's the next part how do we then
6:31 use that value okay so PI if we notice
6:36 here we give it a name as well so I gave
6:38 this PI a name of REM because that's
6:41 what we're calculating we're calculating
6:43 the REM value of the pixels so the next
6:48 bit is we want to display this value on
6:50 the page so how do we do that so there's
6:54 two ways we can do that if we click in
6:57 the PI settings you'll notice that
6:58 there's this show snippet setting here
7:01 if I click on that you'll see that we
7:03 have a snippet here and basically this
7:06 HTML snippet if we put it anywhere on
7:09 the page
7:10 pi will replace that with the actual
7:15 contents of the PI or so that the
7:17 results of your formula okay now if you
7:20 look inside there you'll notice that
7:21 there's also a class pi - R M we can
7:25 actually take that if you and if you
7:27 notice all that is is PI Dash and then
7:30 the name that we defined inside the PI
7:33 settings
7:33 okay so pi - REM if I put that as a
7:36 class on anything it will replace that
7:41 contents with PI so I have two examples
7:44 here here is a header stack and if
7:47 you'll notice this header stack has a
7:48 lot of text in it okay and this actually
7:51 the text here actually displayed you
7:53 know describes what PI is going to be
7:55 doing for us but if we look at the
7:57 settings again this is just a standard
7:59 Foundation header stack I can add a
8:01 custom class and I add PI REM to the
8:05 class list
8:08 and if we preview this page again you'll
8:10 notice that here inside it's going to
8:13 take that header and it's going to
8:15 replace the contents of it with the
8:17 value that PI calculated
8:21 now let's look at this second one if we
8:24 look at this here's another header and
8:25 this it's a little bit different here I
8:28 added some text REM conversion : and
8:31 then I added the span that was from the
8:37 snippet so span class equals PI REM
8:39 close span and then I added REM at the
8:42 end so what PI is going to do is inside
8:45 of this span it's going to insert the
8:47 number that we wanted basically the
8:49 results from our formula and that's
8:52 exactly what happens
8:55 and whenever I change the value pi
8:58 notices that I change the value and it
9:01 immediately recalculates and refills in
9:04 these fields for us dynamically on the
9:07 fly
9:08 so now let's go ahead and jump into demo
9:11 2 here we have a slider and I've given
9:14 that a field name of slider okay and
9:17 let's look at our first pie this first
9:19 pie I've given it a name of triple and
9:22 what I've done is in my formula I've I
9:24 grabbed the value of the slider input
9:28 right with curly brace curly brace
9:29 slider and close those curly braces and
9:32 I multiply that by 3 now notice here
9:35 multiplication is an asterisk
9:37 not an X right so that is common in in
9:42 all programming languages where
9:44 multiplication is actually defined by an
9:46 asterisk so that's how you do your
9:48 multiplication so I'm taking my slider
9:49 value and I'm multiplying that by 3 now
9:54 let's look at the next one right this is
9:56 a little bit different we have something
9:58 called math dot round and then I'm doing
10:01 the same formula as above so I'm doing
10:03 slider times 3 what is this math dot
10:07 round well pie in your formulas you can
10:11 actually use the entire JavaScript
10:13 programming language directly inside pi
10:17 and so that gives us a lot right it
10:21 gives us a lot of really cool baked in
10:23 mathematical functions that JavaScript
10:26 has and these this one here is math dot
10:30 round so this is your typical it will
10:33 round the number up or down so if the
10:35 number is greater than you know 0.5 it
10:39 will round the number up and if it's
10:42 less than 0.5 it will round that number
10:43 down right so let's see that in action
10:49 here we'll notice that we have 2.25 and
10:52 when we triple that it is 6.75
10:56 well rounding will now round that number
10:58 up because it's closer to 7 and if we
11:01 keep going here we have 8.25 well that's
11:04 it we'll round that number down because
11:06 it is actually closer to 8 right so
11:09 that's what rounding does so if we go
11:11 back we'll notice that I did give this
11:13 pi a name of round and let's look at
11:16 some of the other ones we here we have
11:17 ceiling I give this a pine name of
11:19 ceiling and this is a little bit
11:21 different right
11:22 essentially what ceiling does is it will
11:25 always round up so it'll always go for
11:27 the bigger whole number but there's
11:29 something else different about this
11:31 instead of me putting in the slider
11:33 times 3 I put in triple
11:38 so essentially what I'm doing is I'm
11:40 telling this pie go ahead and pick trip
11:43 the value of triple which is the first
11:46 pie that we have here and use that
11:49 this is powerful because it allows PI's
11:52 to reference other PI's right so here
11:57 triple does slider times three and
11:59 instead of doing slider times three
12:01 again I could just simply reference
12:04 triple so now I can use both values if I
12:09 needed to now if you only need to use
12:12 one value if you never need to know it's
12:14 what triple is exactly then maybe you
12:17 just do it all in one but if you need to
12:20 have access to both numbers it is very
12:23 powerful that Pi allows you to reference
12:26 other PI instances by name very cool
12:30 let's go down and here we have math dot
12:32 floor and we're referencing triple again
12:34 and that essentially will always round
12:37 down so even if it's five point nine it
12:40 will always return five it always goes
12:42 down this next one is a little bit
12:46 trickier right the syntax is a little
12:47 bit different than our math dot syntaxes
12:50 but here we surround our triple in
12:53 parentheses and then we do dot two fixed
12:57 one and what this is gonna do is it's
12:59 gonna round to the nearest one decimal
13:02 place so let's see all of those in
13:05 action here if I go here we'll see that
13:07 here I have nine point seven five
13:09 rounding gives us ten ceiling gives us
13:12 ten because it always rounds up floor
13:14 will give us nine because it always
13:16 rounds down and then our decimal gives
13:18 us nine point eight because that is the
13:21 closest decimal for one decimal place
13:24 pretty cool now to create all those
13:27 values that we were just looking at here
13:29 if we double click in these you'll
13:31 notice that I have triple and then I use
13:33 the little snippet right and then round
13:37 I have round colon and then I use the
13:39 little snippet very simple and again to
13:43 see those snippets we just simply go
13:44 into our PI stacks you can click the
13:47 show snippet and there is the snippet
13:49 that you need to display the value of
13:52 that particular PI stack
13:55 so here we are in demo three and here
13:58 we're gonna do a little bit of geometry
13:59 so in demo three we take a number input
14:03 that we assign the name radius so this
14:06 number input has a name of radius and
14:08 that is gonna be the radius of our
14:10 circle now if you ever take in geometry
14:12 hopefully you have you'll notice that
14:14 the two famous equations for these are
14:16 the perimeter is two PI R and the area
14:19 is PI R squared right so if we look at
14:23 the PI here I gave this obviously a name
14:25 of perimeter we are gonna do a little
14:28 bit of math so here we have two times
14:31 math dot pi now this is a little special
14:35 thing you'll notice you've never seen
14:36 this one before
14:36 this is another little bit of JavaScript
14:38 math dot pi is a special constant that
14:42 you can use if you want to actually use
14:44 pi right because you could type in 3.14
14:48 which most people do but as you probably
14:50 know pi is an infinite number it's three
14:53 point one five one six I'm not even
14:57 gonna continue going I don't know what
14:59 it is but it is a big number that goes
15:01 on for infinite so math dot pi is a very
15:06 useful constant that you can use that's
15:08 baked into JavaScript so we're doing two
15:12 times math pi times radius and that
15:15 obviously gives us our perimeter
15:21 our next one calculates the area of a
15:24 circle and you'll notice in here we have
15:27 a little bit more complex right we have
15:30 math dot pi times and here's a new math
15:34 function here math pow
15:37 this essentially gives us the power to
15:40 right so we have radius and two so that
15:45 does the radius squared so we have
15:48 radius to the power of two and then if
15:52 you notice inside there I do
15:55 parentheses and then I do to fixed to
15:58 now you might want to ask why did you do
16:01 that
16:01 because let's go ahead and I'm going to
16:04 remove this two fixed too
16:08 and we're gonna do simply PI R squared
16:12 so we have pi radius squared um let's
16:15 see what the results of that are if we
16:17 notice here it gives us a big number
16:20 right with lots of decimals so what if I
16:23 only want to have two decimal places
16:26 that's exactly what that two fixed
16:28 syntax does for us so let's go ahead and
16:30 add that back in I'm going over here
16:33 we're gonna add parentheses around the
16:35 entire thing and then do dot two fixed
16:40 and I want two decimal places and we're
16:44 gold in
16:49 there we go so now I have in my area I
16:52 only have two decimal places now
16:56 very cool now just as you saw before in
17:00 order to get these values onto the page
17:02 I just simply use the snippets again so
17:05 you're a have P equals and then I use
17:07 this snippet from the parameter stack
17:09 right again to see that we go to the PI
17:12 we go show snippet and there is my
17:14 snippet that I need to add on to the
17:17 page in order to see the value and we
17:20 did the same thing here for area we have
17:22 span class equals PI - circle area and
17:26 that will then display that so as you
17:29 see pi is really simple to use
17:30 now this last example there was a little
17:33 bit of tricky syntax there was a lot
17:34 going on in there right and so what can
17:37 we do to make that a little bit easier
17:40 to read and create right and basically
17:43 what I recommend is you could
17:45 potentially if you want to do something
17:46 a little bit more complex rather than
17:48 just you know field times three is you
17:52 could definitely use your own kind of
17:54 text editor to edit these things right
17:56 just makes it a little bit simpler to
17:58 use so I'm gonna show you the example
18:00 maybe a couple examples with some apps
18:02 that you probably might have on your own
18:04 machine I'm gonna show you one with
18:06 TextEdit and then I'm gonna we're gonna
18:09 move over and I'm gonna show you what I
18:10 use an app called vs code that allows
18:14 you it's free to download but I'm gonna
18:16 show you kind of the benefits of using
18:18 either of those so as I just said if we
18:22 look at this particular formula from
18:23 demo three and we open that and we want
18:26 to edit this it could get really hairy
18:28 right so what we're gonna do is I'm just
18:31 gonna copy this so here we are in
18:34 TextEdit this is on everybody's Mac and
18:37 we can use this now I recommend that you
18:41 use a mono space font when you're
18:43 looking at this stuff it just makes it a
18:45 little bit easier to look at right
18:46 so from here um you probably should have
18:49 Monaco and let's just go ahead for this
18:52 video I'm gonna make it big let's make
18:54 like 24 pixels and I'm gonna paste that
18:57 in so here we are as you see this is
19:00 just a little bit easier to read and
19:02 look at sometimes you can add some
19:04 spaces to kind of give us some context
19:07 of what we need right
19:10 so if we notice here we have math dot pi
19:13 times and then we have math dot POW and
19:16 that math up power requires that it's
19:18 inside two different brackets and then
19:22 here we define our radius by giving our
19:25 curly brackets and then we have a comma
19:28 because we have to provide the radius or
19:30 a number and then the power that we want
19:33 to do so we're going to do the power of
19:35 2 for radius and then basically I want
19:39 to take that value
19:41 and then I want to do to fixed right so
19:45 essentially what we're doing is I'm just
19:47 going to go ahead we're doing this this
19:50 gives me a value that has a big huge
19:53 decimal number then I'm placing that
19:56 inside of parenthesis so here's open
19:59 open parenthesis close parenthesis and
20:01 then I'm doing dot two fixed and then
20:05 we're doing I want two decimal places
20:07 so we're getting a little bit advanced
20:10 here right because um in JavaScript
20:13 syntax matters and essentially if if you
20:18 lose any of this so let's say I forgot
20:21 that closed parenthesis pi will break
20:25 this will break your page and be careful
20:29 because it is very sensitive to syntax
20:34 you have to have your syntax down
20:36 perfect so that everything will work so
20:41 here we are in the code editor that I
20:43 use on a daily basis it's called vs code
20:45 and this is what I use to develop stacks
20:49 and websites and stuff every day so um I
20:53 like vs code because if you notice it
20:55 gives us a little bit of syntax
20:56 highlighting so when I pasted this on to
20:58 the page down at the bottom here you can
21:00 define that this is actually JavaScript
21:02 and then kind of give us us gives us a
21:04 little bit of help okay now this curly
21:07 brace curly brace is kind of a PI
21:09 specific thing so you'll see you might
21:11 see little red things on there but
21:14 because that isn't technically
21:16 JavaScript that's a little bit of
21:17 additive stuff on top of JavaScript for
21:20 PI to work but it does gives us a nice
21:23 little you know helper in terms of the
21:27 nice syntax highlighting and stuff like
21:28 that another thing it does so remember
21:30 we wanted to add this two decimal places
21:32 so what I do is here at the beginning
21:34 I'm going to do parentheses now you do
21:36 close parentheses and if you notice um
21:39 it did give me a little red thing saying
21:42 hey I expected a parenthesis there okay
21:46 that's pretty cool so now I add the
21:49 parentheses and that little red thing
21:50 goes away because we're syntactically
21:52 correct now and then I do dot
21:55 and what's cool here is that um vs code
21:58 gives us things that we can do right so
22:00 I could do a look to fixed and then I
22:03 know I have to do parentheses and it's
22:05 telling me I have to pass a number so I
22:07 can do number two pretty cool if we
22:10 hover over these you'll notice that um
22:12 it didn't it didn't like these curly
22:14 braces it didn't expect that expect that
22:19 with PI you need these for pi but your
22:21 code editor might say hey I don't
22:23 understand that but everything else the
22:26 errors that you know they give you let's
22:28 say if I delete that that parenthesis
22:31 it's now going hey something's wrong
22:33 you're missing a parenthesis somewhere
22:34 right so very cool I recommend that you
22:39 use vs code if you're gonna do any sort
22:41 of complicated math and then basically
22:44 all you have to do is you just copy this
22:46 head back into rapidweaver and just
22:49 paste it directly into pi and you should
22:53 be good to go so as you see pi um it
22:57 can't get complicated if you want to
22:58 start doing your own javascript okay now
23:01 just a word of note while pi allows you
23:05 to build on some really complex and
23:09 amazing things I cannot help you write
23:13 your javascript you know if PI works
23:17 great um you know test that with
23:19 something simple like my value plus one
23:21 or something like that if it works
23:23 awesome chances are if it doesn't work
23:26 when you put in your complex JavaScript
23:28 or the page breaks it means something is
23:31 wrong right
23:32 um and I cannot help you write
23:34 JavaScript i I just don't have the time
23:36 or resources to help people a thousand
23:38 people you know develop the things so
23:41 what I do recommend is if you have some
23:43 issues with your JavaScript inside PI go
23:47 ahead and create a post on Weaver space
23:48 and um you know there are a lot of
23:51 really smart users as well as I will
23:53 attempt to help you you know create
23:56 things that you want but officially
23:59 please don't be emailing me that your
24:02 JavaScript is broken and that you can't
24:04 get your formula working pi is a
24:07 powerful tool
24:09 um but I can't help you code I give I'm
24:11 giving you the power to use that right
24:15 so I hope you enjoy it use your power
24:18 wisely
24:19 I can't wait to see what you build with
24:21 it I hope that this basics of Pi really
24:24 gets your head around PI play around
24:27 with it and we will have a lot more
24:29 videos on more advanced stuff to do with
24:32 PI as well so hope you enjoy pi we'll
24:35 talk to you later bye"}]