Quickly with Python - 01 - Basics, Installation and Maths Video Lecture | Python- Mastering Development in Python - Software Development

good morning and welcome to let's learn
this is t-pain speaking and i am going
to be teaching you all about python and
with this series of tutorials i'm going
to actually be covering a whole bunch of
topics ranging from very basics to
advanced topics later on down the line
and what I want is for you to follow
along with me and work with me as we do
this because that is how you're going to
get the most out of this
first let's I'll go through a whole
bunch of theory and explain this to you
and then we'll start diving right in so
first of all what is Python Python is a
flexible programming language so why I
learn it it can do so much it's free it
works on Windows Mac Linux you can build
custom scripts for Maya MotionBuilder
nuke they all support it you can go into
game development with it you can bind it
to user interfaces for tool development
you can script everyday tasks for the
web for file organization for Excel even
if you wanted to it has so much
potential it's easy to learn and it
looks really good on your resume okay so
where you download it you download it
here on Python org slash get it so the
version that we're going to be working
with is two point seven point three and
you can find that below three point
three right here and it's free to
download and it plugs right into just
about any platform you need so where to
get help if you're ever like at all
struggling with Python just start
searching on Google with Python and then
whatever your problem is whether it be
sine you're looking for signs then boom
you can go into mathematical functions
there's tons of forums on Stack Overflow
dedicated to Python look there so after
you download and install Python you
should install it in the main directory
the C Drive was mine and it's going to
be right here under Python two seven and
then if you want to you can follow along
with python exe which will open up the
command line or the terminal if you are
Mac or you can open
idle which is what I'm going to be using
and it comes built right in when you saw
Python alright so here we are in idle so
variables are containers for any kind of
data so I want you to type in ver var
equals 5 enter ok this is your way of
assigning a variable you type in first
whatever you want to name it then an
equal sign and then the value wish to
store so if I type var ENTER it outputs
5 the value I have assigned to us so now
that value is bound to that variable I
can assign any number of types of
variables which we will get into later
but for now we're just going to work
with integers so I can name it anything
I want and it will stick I can name in
just a whole bunch of garbage like SDF
SDF equals 5 equals 4 and if I punch in
that again that value will be spit back
out now this is where naming is very
important you want to be as explicit as
possible with your naming meanwhile like
being pay attention to the
capitalization for one of my preferences
and preference I've seen for a lot of
Python programmers is variables start
off lowercase for the first word and
then capitalize the first letter of the
next word so if I were to type a big
foot that's exactly how I type it bit
lowercase big uppercase F and then
lowercase but equals 4 so I want you to
type in big foot 4
it's a good practice to get into and
then type it again to make sure that the
value is stuck be careful not to include
any spaces in your variable names so big
foot could type in big space foot equals
5 or 35 or whatever
and you'll notice you get a syntax error
and what this means is that there is
some sort of error that like in the way
you typed it in and the reason being is
because I included that space in between
big and foot so go ahead and try that
one more time big foot with a space in
between equals 56 or whatever and you'll
get that same error so don't include
spaces and store it stead just
capitalize the first letter of every
other word so big boot he goes for there
we go excellent work so we know that we
can assign values with the equal sign
now we can also re assigned values with
the equal sign so I'm going to go ahead
and say big capital F foot is equal to
seven and I'm going to type big foot
again go ahead and try that yourself
type in big capital F foot big foot is
equal to seven and then type it again
and you'll see that the value is
reassigned all right now we're going to
begin on with my favorite topics math so
python has a built-in math function that
you can just punch right in so let's
type in five plus five what do you think
is going to happen ten good job you
guess correctly it actually will spit
out the answer depending on what it is
so I can do like two plus four or four
plus six and that will give me the
answers you can also do a 4 minus you
can do the standard math operations you
can do multiplication and it'll figure
it out I want you to try out a couple
different math operations the plus the
addition a subtraction division and
multiplication star is for
multiplication so we can go 32 times 32
enter try that 32 divided by 32 try that
now we're going to get into something
that is very important what I want you
to do now is type in 3/2 what do you
think
is going to happen all right
3/2 if you punch it into a calculator
would be 1.5 but here it punched out 1
it returned a value of 1 now what's
going on is it's interpreting the values
as integer values integers are simply
numbers without decimal points they're
whole numbers floating values or
floating point values are numbers that
have a decimal point somewhere in the
value thus the name floating point is
that dot can be anywhere in the value so
go ahead and try that real quick type in
100 point 0 enter and you'll see that it
sticks out that point 0 at the end
that's its way of saying hey I know this
is a floating point value try just
typing 100 now and you'll see that there
is no decimal point note that it
maintains the point 0 at the end of it
this is the difference between integers
and floating points so now let's try
that 3/2 again but this time we're going
to 3/2 point 0 enter and now we get the
correct answer this is the difference
between integers and floating points if
python is given one value that's a
floating point it'll convert everything
else to a floating point or it'll try
its best it's best to explicitly say
it's a floating point by adding a point
0 at the end of it if you can another
way you can do that is we can actually
punch in a explicitly of
two floats and the way you do that is
you type float parentheses 3 close
parentheses divided by 2 and now it'll
convert one of those values that will
convert the 3 to a floating point value
and they'll stick so try that try
punching in float parentheses 5 close
parenthesis divided by 4
enter and now we get one point two five
which is the correct answer the same can
be done in the reverse so we typed in
floats open closed parentheses to
convert an integer or some value into a
floating point value okay so we can also
do the same of converting a float back
to an integer value using int open
closed parentheses with 3.0 inside type
that and now we have a integer value
returned so int open close parentheses
so this is how you solve for rounding
errors some other math operations you
may want to know about is the remainder
and the way you use that is you type in
5 % 4 so go ahead and type that in and
then press Enter
so what this is saying is how much
remains after I take in take out a whole
bunch of number fours out of 5 1 remains
so another example of this would be like
if I were to punch in 10 % 5 go ahead
and type that in and what you get out is
0 because 10 is divisible by 5 go ahead
and type 11 % 5 and you'll be spit out 1
it's because one overflows so the
remainder is very useful for when you're
doing loops and a number of other
operations will do down the road so next
we're going to learn about powers and my
favorite way to assign power values is
using star star so we're going to type
twelve star star to enter and now we get
144 that's 12 squared because we just
decided the square value and you can
assign this for square roots as well so
I'm going to type in um 16 star star
zero 0.5 go ahead and type that in press
Enter so
take note that it converts everything to
a floating-point value when a
floating-point value is passed in so we
get out 4.0 which is the square root of
16 perfect
so back in algebra you may have learned
that you can use parentheses to close
off specific parts of the algebra the
same works in programming so if I type
five times parentheses 5 plus 5 close
parenthesis enter it works the exact
same it adds the two 5s first that are
closed within the parentheses and then
multiplies them by the other 5 and so we
end up with 50 so it's 10 times 5 is 50
so parentheses worth the exact same so
there's a number of other math functions
that you can use like the absolute value
sign value cosine value floor ceiling um
etc from the math import section alright
guys great job keeping up today you did
an excellent work alright so here are
some examples for you I want you to
discover for yourself what they actually
do a lot of the greatest programming
comes out of curiosity so be curious if
you liked the video or have any
questions please leave me a comment I'll
be sure to get back to them when I can
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