Learning the Basics of Python Programming | CMD TO

 Learning the Basics of Python Programming | CMD TO

Now it is time to get to know a bit more about Python programming and how

you can make it work for you. You will need to learn a bit more about the

different keywords and the variables that come with Python so you are able to

write the words that you want and make the program perform in a certain way.

Let’s take a look at some of these basics of Python programming so you can

get started with your new code right away.

Keywords

When you are working on a new computer coding program, you are going to

notice that each computer language will have certain keywords. These are the

words that are meant for a specific command or purpose in the language and

you should try to avoid using them anywhere else. If you do use these words in

other parts of your code, you may end up with an error alert or the program not

working properly. The keywords that are reserved for Python include:

And

Pass

Or not

Nonlocal

None

Lambda

Is

In import

If

Global

From

For

Finally

False

Except

Else

Elif

Del

Def

Continue

Class

Break

Assert

As

Yield

With

While

Try

True

Return

Raise

Identifier Names

When you are creating a new program in Python, you are going to work on

creating quite a few entities, a combination of functions, classes, and variables.

All o these will be given a name that is also known as an identifier. There are a

few rules that you need to follow when forming an identifier in Python

including:

It should contain letters, either uppercase or lowercase or a combination

of the two, numbers, and the underscore. You should not see any spaces

inside.

The identifier can’t start with a number

The identifier can’t be a keyword and it shouldn’t include one of the

keywords inside.

If you break one of these rules, the program will close on you and will show a

syntax error. In addition, you need to work on making identifiers that are legible

to the human eye. While the identifier may make sense to the computer and get

through without causing issues on the computer, a human is the one who will

read through the code to use it themselves. If the human eye doesn’t understand

what you are writing in a certain place, you could run into some issues. Some

of the rules that you should follow when creating an identifier that will be

readable to the human eye include:

The identifier should be descriptive—you should pick out name that is

going to describe what is inside the variable or will describe what it

does.

You should be careful with using abbreviations that aren’t necessary

because these always make things that are difficult.

While there are a lot of ways that you can write out your code, you should be

careful and stick with one rule throughout. For example, both MyBestFriend

and mybestfriend work in the coding world, but pick one that you like and do it

the same each time that you work in the program to avoid confusion. You can

also add in underscores into this or numbers, just be careful that you keep

things consistent.

Flow of Control

When working on the Python language, you are going to write out the

statements in a list format, just like you would when writing out a shopping list.

The computer will start with the first instruction before working through each of

them in the order that you make them show up on the list. So you will need to

write out the controls that you want just like you would for your grocery

shopping list to make sure that the computer is reading it properly. The

computer will only stop reading through this list once it has done the final

instruction to completion. This is known as the flow of control.

This is an important way to get started. You want to make sure that your flow

of control is even and smooth for the computer to read. This will make it easier

to get the program to do what you would like without as many issues and

ensures that the computer program doesn’t get stuck, cause issues, or have

something else go wrong.

Semi-colons and Indentation

When you look at some of the other computer languages, you will notice that

there are a lot of curly brackets used to arrange the different blocks of code or

to begin and end the statements. This helps you to remember to indent the code

blocks in these languages to make the code easier to read, although the

computer will be able to read the different codes without the indentations just

fine.

This type of coding can make it really difficult to read. You will see a lot of

unnecessary information that is required for the computer to read the code, but

can make it hard on the human eye to read this. Python uses a different way of

doing this, mostly to help make it easier on the human eye to read what you

have. You are going to need to ident the code for this to work. An example of

this is:

# this function definition begins a new block

def add_numbers (a, b):

c= a + b

# as is this one

return c

# this function definition begins a new block

if it is Saturday

print (It’s Tuesday!”

# and this one is outside the block

print (“Print this no matter what.”)

In addition, there are a lot of languages that will use a semicolon to tell when

an instruction ends. With Python though, you will use line ends to tell the

computer when an instruction will end. You will be able to use a semi-colon if

you have a few instructions that are on the same line, but this is often

considered bad form within the language.

Letter Case

Most computer languages will treat uppercase and lowercase letters the same,

but Python is one of the only ones that will be case sensitive. This means that

the lower case and upper case letters will be treated differently in the system.

Keep in mind as well that all the reserved words will use lower case except for

None, False, and true.

These basics are going to make it easier to get started on the Python

programming. You need to take a bit of time to go through the program in order

to get familiar with it. You aren’t going to need to become an expert, but getting

familiar with some of the text interpreter and some of the other parts of the

program can make it easier to use and you can learn how the different buttons

will work even before you get started. Try out a few of the examples above

first to help you get started.

Python works to keep things as basic as possible because it understands that

most of its users are going to be beginners or those who are tired of other

complex languages. As you can see here, and in the following chapters, there

are simple commands that you will be able to put forward in order to get the

program to work a specific way. Study these and you can make a great program

without quite as much work.