So hello again and welcome back.
This lesson is going to be a very quick wrap up of a few things that I think I still missed as I was
going through the lessons.
If you remember at the beginning of this section I told you that by the end of this section you should
know almost everything that I'm doing.
Any definition any declaration any specific target they didn't explain in the earlier lessons was supposed
to be you know clear in this particular section.
And as I was going through the lessons I realized there's still a few really quick stuff that I might
have to explain them before we go to our upcoming sections.
So with that in mind I'm going to go ahead into ex-cult and I should mention that while while I was
in order coding the last lesson on this one I have between these two I have updated my export I'm using
export 10 the CD version not the any of the Beatle versions so that doesn't really make a difference
in what we are doing but you might notice some visual you know differences.
In any case I'm going to make in your OP the wrath of swift and in Rap-Up see if I want to explain essentially
a few different things.
One of them is the difference between a float and a double.
The other thing that I want to talk about is marking your application and that's essentially making
the regions.
And finally I want to talk about NSA numbers which is essentially a subclass of an that's of value.
So let's go ahead and quickly have a look at those.
The difference between a float and a double if it doesn't come up somewhere in the lesson so far is
that float is tilted to a floating number two that were spaces and double is 64.
So essentially double provides more numbers and more precision I could do a quick test for you saying
let my float.
Let's make that a float value of 1 divided by three fewer than one divide by three essentially becomes
point 3 3 3 3 3 3.
And in mathematics it becomes point 3 3 forever.
In computers we have to eventually at some point stop that Wedel the same thing.
I'm going to call this one my double.
And that becomes the double of the same thing.
Let's go ahead and princedom.
So I'm going to say print float is the one that is going to be my float on under the cockpit not on
in here.
I'm going to say double is I don't want to put my up in the print file.
So let's go ahead and run this project for application.
This is one of the defense says they're visual things in the new ex-coach essentially shows you the
region you have caused changes since the last save.
So in any way any case float is now point or three up to like you know eight places I guess and double
it's going to be a lot longer.
And that's essentially for when you need more accuracy with your numbers.
I usually get away with just using float values because you know that's.
It does happen occasionally but not very often.
I need a double value.
The next thing is using a..
Number and this number is essentially every four encapsulates a value of the type integer flawed or
or bully and even are assigned value into another entity which offers us a raise for formatting values
and ways for using the value of that time to communicate that value with backbends or different places
and this number is a subclass of an asset value like dimension and values and a value for maintaining
things such as a struct or things such as C.G. points or CGI Rexes or all things that you're going to
see in writing.
Our next section.
But for here all I want to do is I want to use this number two to formats my double in two different
ways of showing it.
I don't want to see it the decimal points.
Maybe I want to see it in a scientific method or other ways.
So to do that I'm going to go ahead and say let's use a large double and I'm going to say large double
is my number one deployed by one through the power of so many many many numbers.
A very very large value.
So the next thing is I'm going to say Let my and this number and what I'm going to make to become any
number of the value and the value is this one the very large one.
And now this.
And this number allows me to do things such as formatting them.
So for instance I could go ahead and say my form either form or other it becomes a number for my other
and I'm going to go ahead and say my form either god number or style is going to be number four.
Neither does the style dots.
And we could look at different ways of showing Clancey showing give the decimal ordinal roll values
or like scientific and religious scientific for now and then they could say I could say Let let's call
it the result value and this is going to be a string.
I'm going to say that's going to be my form are there not a string of.
And a number and that is my answer.
Number two is essentially saying get the number that is produced of a large double called my larger
number get the number of IT COME both into a string using a format there that converts values into a
scientific style.
Put it in the reservoir.
And of course they could go ahead and say preens rez is Reds land and not this holiday.
It's there is and we get that warning is obviously because it has value is optional.
And I think optional 3.3 retreat is the power of 10.
And if I wanted I could simply go ahead and say it's an unwrapped optional so that thing doesn't happen
anymore.
So I can run it for more time.
And now we will see three point three.
The power of 10 and that's a scientific way of showing this number.
Let's try another one let's say your style I want is let's say currency.
I honestly don't know what's the difference between crying and saying crunchie accounting so we can
try both of them.
So currency is going to be separated by every tear.
The number I'm guessing yes is going to be dollars 9:33 I guess.
Billion 333.
So on and so forth.
And there's another one currency Konting Let's see what's the difference between this one and one.
So depending on the sign that you might need you could use any of those up.
Now with that in mind the last thing was marking or regions.
So a lot of times in your court.
And that is in just one single file.
You want to be able to separate your code into separate pieces for instance.
I have a region up there that is my variable declarations and then I have another region which is my
delegates.
And then when I have another region which is I don't know my method definitions.
So for each of these we essentially introduce a new region on industry if we do it it's my comments
Mark or capital letters.
And then in front of the market you're right.
I don't know valuables it's not the moment they do this up here in the selections I could actually see
it showing up that you know if I'm here at the bottom of my court and I both too valuable it pushes
me up they're there to put different types of marks as well.
One of them is called the Mark sorry it's called to do.
And that's essentially something you have to do in here.
That's essentially making your way for you to know that these are the things that you still have to
implement.
So could go ahead on that one and there's another one called The Fix me which is essentially something
that has gone wrong.
You can write yourself.
I don't know let's put this at the bottom of the code so here.
And if I go to selection's I say overawing there is something you have to fix in here.
It's a very good way of organizing your call and then reminding yourself of things that are coming up
just like how you use comments simply for reading different things and knowing what's going on and you
could use Mark to do and fix me to a specifically you know look for something that you want to do if
you want to use these in Objective C it's a little bit different.
It's called tracking you more March and that's how we essentially make different regions even in Objective-C.
But I'm guessing that for the most part you guys will be doing Strief from now on.
So our difference between float and double are using a number on using regions with daddy in mind.
Let's move on.