Ruby Programming Tutorial - 19 - Changing Data Types Video Lecture - Introduction

alright guys welcome to your 19th Ruby
lesson and in this lesson I'm gonna talk
to you guys a little bit more about
numbers and teach you guys how to format
numbers to give you guys the answer that
you want so let's go ahead and recap
what we know already we already know if
we input something like 13 divided by 4
then Ruby's going to think that since
we're asking it in integers then we want
an in as your answer so even though the
answer to this question is three point
two five it's going to say hey three
close enough you asked them integers you
want to injure so we say okay now that
we want the exact answer
let's just go ahead and do thirteen
point O divided by four point oh now
whenever we ask it like this it gives us
the exact answer three point two five
why because we asked with floats or
numbers with decimal points but here's
the thing as the programmer we know
what's going on behind the scenes and we
know that we can kind of tweak Ruby and
trick it into giving us the right answer
but say that we built this program such
is you know a simple calculator or
something well the user of that
calculator doesn't know that you need to
ask it numbers with decimal points what
they're going to do is they're gonna you
know maybe input a variable like 13 for
a in 4 for B and then they're gonna go
ahead and say okay print out a over B
and it's gonna say 3 and then I'm gonna
say hey this frickin calculator is
broken what's wrong with this well what
we need to do whenever we're programming
these things like simple calculators or
anything what we need to do is change
the data type we need to take their
integers and we need to change them into
floats so how do we do that well in
order to do that we need to use a method
called 2f and this method pretty much
takes an integer and it turns it into a
float so let's go ahead and run this
baby again so say that we made the same
thing like C equals I'll use the same
values C equals 13 and B or excuse me
equals four well now what we wanted to
do is we want to go ahead and print out
the answer on the screen but instead of
just writing C over D what we wanted to
do is put C to underscore F and whenever
we do this here's what's going on it's
gonna frickin throw every time I'm doing
these tutorials my freaking throat dries
out what it's gonna do is it's gonna
take C which is 13 and it's gonna call
the method 2f now the method 2 X takes
the value which is 13 and it changes it
into a floating-point number so it's
pretty much gonna say okay this 13 is no
longer integer it's now a float so now
whenever we try to print it out Ruby
knows that we want to work with floats
and the cool thing about this is
basically the user can still input
integers but behind the scenes we're
changing it to floats so now with this
technology we can build programs that
are a lot more user-friendly and a lot
more precise so let me go ahead and
finish up this mini program D to
underscore F I always try to write tofu
for some reason so basically even though
the user inputted 13 in for what's
really going on is we converted that to
13 point O and 4.0 and check it out they
now get the correct answer of three
point two five even though they asked it
in integers so there you go that is how
you take one data type and change it to
another type of data and by the way this
isn't the only method to F there are
different types of um well I guess I
might as well explain this whenever you
change one data type to another data
type in computer programming
it's called casting so just remember
that and I'm just gonna shut up and go
get a drink of water or something and
I'll see you guys in the next video so
thanks for watching and I'll see you
then