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Python is the ultimate way to go
It is relatively very easy to install python on windows, macOs and different varients of Ubuntu. Details could be found on this LINK
The very first question that came in our mind is WHY PYTHON?, why not some other programming language. If you’re going to write programs, there are literally dozens of commonly used languages to choose from. Why choose Python?
Here are some of the features that make Python an appealing choice.
- Python is Popular: That's make it easier to work as a team as everyone can talk the same language.
- Python is Interpreted: This makes for a quicker development cycle because you just type in your code and run it, without the intermediate compilation step.
- Python is Free: The Python interpreter is developed under an OSI-approved open-source license, making it free to install, use, and distribute, even for commercial purposes.
- Python is Portable: Because Python code is interpreted and not compiled into native machine instructions, code written for one platform will work on any other platform that has the Python interpreter installed.
- Python is Simple: As programming languages go, Python is relatively uncluttered, and the developers have deliberately kept it that way.
Python is a high-level language. It is considered as an interpreted language because Python programs are executed by an interpreter. There are two ways to use the interpreter:
- command-line mode
- script mode
A high-level language is any programming language that enables development of a program in a much more user-friendly programming context and is generally independent of the computer's hardware architecture.
A program is a sequence of instructions that specifies how to perform a computation. The computation might be something mathematical, such as solving a system of equations or finding the roots of a polynomial, but it can also be a symbolic computation, such as searching and replacing text in a document or (strangely enough) compiling a program. For more details, please see the book How to Think Like a Computer Scientist: Learning with Python
Programming is a complex process, and because it is done by human beings, it often leads to errors. For whimsical reasons, programming errors are called bugs and the process of tracking them down and correcting them is called debugging. Three kinds of errors can occur in a program: syntax errors, runtime errors, and semantic errors. It is useful to distinguish between them in order to track them down more quickly.
I am hoping that you must be familier with the basics of programming (if you are new to programming, see this tutorial), we will directly start using python and you can learn/refresh your concepts on the go
Before making your hand dirty with a real coding example, we need to choose the integrated development environment to write a python program. A list of different IDE's could be found on LINK. We will be using visual studio code for our purpose with Python extension installed on it.
On Windows machines where you have already installed Python from the Microsoft Store, the python3.10 command will be available. If you have the py.exe launcher installed, you can use the py command. Just type py in the VS code terminal and it will show the version of python installed Python 3.10.6
You can write small code in the interpreter and check the output
>>> the_world_is_flat = True
>>> if the_world_is_flat:
... print("Be careful not to fall off!")
...
Be careful not to fall off!
The interpreter can be used as a calculator very easily. It can easily add numbers, like
>>> 2 + 2
4
>>> 50 - 5*6
20
>>> (50 - 5*6) / 4
5.0
>>> 8 / 5 # division always returns a floating point number
1.6
The integer numbers (e.g. 2, 4, 20) have type int, the ones with a fractional part (e.g. 5.0, 1.6) have type float.
The equal sign (=) is used to assign a value to a variable. Afterwards, no result is displayed before the next interactive prompt:
>>> width = 20
>>> height = 5 * 9
>>> width * height
900
If a variable is not “defined” (assigned a value), trying to use it will give you an error:
>>> n # try to access an undefined variable
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
NameError: name 'n' is not defined
The interpreter can be used for working with strings and lists. Working with indexes of strings and lists is really important concept to learn. Strings can be indexed (subscripted), with the first character having index 0. There is no separate character type; a character is simply a string of size one:
>>> word = 'Python'
>>> word[0] # character in position 0
'P'
>>> word[5] # character in position 5
'n'
Indices may also be negative numbers, to start counting from the right:
>>> word[-1] # last character
'n'
>>> word[-2] # second-last character
'o'
>>> word[-6]
'P'
In addition to indexing, slicing is also supported. While indexing is used to obtain individual characters, slicing allows you to obtain substring:
>>> word[0:2] # characters from position 0 (included) to 2 (excluded)
'Py'
>>> word[2:5] # characters from position 2 (included) to 5 (excluded)
'tho'
List are the most common compound data type. The most versatile is the list, which can be written as a list of comma-separated values (items) between square brackets. Lists might contain items of different types, but usually the items all have the same type.
>>> squares = [1, 4, 9, 16, 25]
>>> squares
[1, 4, 9, 16, 25]
Like strings (and all other built-in sequence types), lists can be indexed and sliced:
>>> squares[0] # indexing returns the item
1
>>> squares[-1]
25
>>> squares[-3:] # slicing returns a new list
[9, 16, 25]
For more details, please see this link
Have you ever heard of Fibonacci Series? Here is a simple python code for that
>>> # Fibonacci series:
... # the sum of two elements defines the next
... a, b = 0, 1
>>> while a < 10:
... print(a)
... a, b = b, a+b
...
0
1
1
2
3
5
8
This example introduces several new features.
-
The first line contains a multiple assignment: the variables a and b simultaneously get the new values 0 and 1. On the last line this is used again, demonstrating that the expressions on the right-hand side are all evaluated first before any of the assignments take place. The right-hand side expressions are evaluated from the left to the right.
-
The while loop executes as long as the condition (here: a < 10) remains true. In Python, like in C, any non-zero integer value is true; zero is false. The condition may also be a string or list value, in fact any sequence; anything with a non-zero length is true, empty sequences are false. The test used in the example is a simple comparison. The standard comparison operators are written the same as in C: < (less than), > (greater than), == (equal to), <= (less than or equal to), >= (greater than or equal to) and != (not equal to).
-
The body of the loop is indented: indentation is Python’s way of grouping statements. At the interactive prompt, you have to type a tab or space(s) for each indented line. In practice you will prepare more complicated input for Python with a text editor; all decent text editors have an auto-indent facility. When a compound statement is entered interactively, it must be followed by a blank line to indicate completion (since the parser cannot guess when you have typed the last line). Note that each line within a basic block must be indented by the same amount.
-
The print() function writes the value of the argument(s) it is given. It differs from just writing the expression you want to write (as we did earlier in the calculator examples) in the way it handles multiple arguments, floating point quantities, and strings.
Besides the while statement just introduced, Python uses the usual flow control statements known from other languages, with some twists
- if Statement: Perhaps the most well-known statement type is the if statement. For example:
>>> x = int(input("Please enter an integer: "))
Please enter an integer: 42
>>> if x < 0:
... x = 0
... print('Negative changed to zero')
... elif x == 0:
... print('Zero')
... elif x == 1:
... print('Single')
... else:
... print('More')
...
More
There can be zero or more elif parts, and the [else (https://docs.python.org/3/reference/compound_stmts.html#else) part is optional. The keyword ‘elif’ is short for ‘else if’, and is useful to avoid excessive indentation. An if … elif … elif … sequence is a substitute for the switch or case statements found in other languages.
- for statement: The for statement in Python differs a bit from what you may be used to in C or Pascal. Rather than always iterating over an arithmetic progression of numbers (like in Pascal), or giving the user the ability to define both the iteration step and halting condition (as C), Python’s for statement iterates over the items of any sequence (a list or a string), in the order that they appear in the sequence. For example (no pun intended):
>>> # Measure some strings:
... words = ['cat', 'window', 'defenestrate']
>>> for w in words:
... print(w, len(w))
...
cat 3
window 6
defenestrate 12
There are lot of learn on this topic and more details can be found here