Perl Tutorial - 4: Scalar Variables Video Lecture | Perl Building Blocks: An Introduction to Perl - Back-End Programming

hello guys welcome to my channel this is
the fourth tutorial in this course and
in this little we are going to talk
about scalar variables and in perl
scalar variables are simply referred to
as scalars and a scalar is nothing but a
single unit of data right so if it is a
number then it is a number if it's a
string it's a string if it's just one
character then it's one character it's
different from the other kinds of
variables that you can have in Perl like
arrays and hashes and the difference is
going to be clear when we get to
tutorials on arrays and hashes right so
for the time being just know that a
scalar variable can hold numeric values
it can hold the string values it can
hold float values as well as integer
values when I talk about numbers and it
can also have octal and hexadecimal
values so for this tutorial we have a
script called scalars and in this script
on line number one we have the shebang
line and let me just talk a little about
this line and you know the reason why I
have it in almost all my scripts is
because I run my Perl code on Linux a
lot right so although I am demonstrating
these tutorials to you on Windows and
you don't really need to put this line
in your script the reason why people who
program Perl code on UNIX or Linux
systems have the shebang line in the
code is that it offers lot of
convenience while running so if you have
this line if this is the first line in
your script then you could just type the
name of your script in the terminal and
the code would run you don't have to
specify the the name of the interpreter
which is Perl so you know it saves a
little bit of effort you don't have to
type the name of the command every time
just type the name of the script and it
will run and this actually is the
location of the polar interpreter in the
UNIX file system so within the user
folder there is a folder called
pin which has all the binary
is and in that folder you will find the
interpreter for purl and as I mentioned
on most Linux or UNIX distributions Perl
is pre-installed so anyway let's get
back to our discussion on scalars on
line number three in the script you can
see that I've created a scalar variable
called rank and in Perl you create
variables using the dollar symbol and
you assign values using the equal to
symbol or the assignment operator I've
given this variable the value 1 on line
number 4 I have created another variable
called name and this one has a string
value Novak and of course you can create
string variables using single quotes as
well as double quotes but if you want
escape sequences to be bundled along
with your string text then make sure
that you create your variables using
double quotes on line number five I have
created a variable called Tod underscore
money short form for total money and
this one is a float value because we
have a decimal point in this number and
we have you know some digits after the
decimal point as well on line number six
we have created an octal variable and in
Perl you create an octal variable by
placing a 0 at the beginning of your
numeric value so you know this is
actually an octal code 1 6 7 you can see
that all three digits in the code are
less than 8 and that's how you figure
out whether it's an octal number or not
but of course the main thing that
distinguishes an octal number from a
regular number in Perl is that octal
numbers are preceded with 0 right on
line number 7 I have created a
hexadecimal scalar variable called my
underscore hex and you create a
hexadecimal number by using 0 as well as
the alphabet X in lower case and then
you can follow this combination with
your code and in our case the code is a
B E and then I have printed these
variables not in the sequence in which I
have created because I'm printing name
before printing rank I have
a new line escape sequence at the end of
each string of text and by now I'm
pretty sure this is like piece of cake
for you guys so I'll just run the script
and show you the output yeah so we see
the name displayed first which is Novak
and then rank has a value 1 and then
total prize money is this floating value
and then this code 1 6 7 in octal
translates 219 in decimal right and then
this code a b e in hexadecimal format
translates to two thousand seven and
fifty in decimal format so that's it
about scalar variables in the next world
we're going to check out you know more
perl features and i hope you guys had
fun watching this video you may
subscribe to my channel if you haven't
already i'm going to see you in the next
one till then take care