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Aatmaj
Aatmaj

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Learning Python- Basic course: Day 2, Statements, Comments and Indentation

✌️Hi all! Welcome to the second day of the course! Today let us learn about some Python syntax.


Statements in Python
Statements in Python are of three types
a) Expressions- Statements which perform actions like addition, division, or any other such operations.
Here are a few sample commands.
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b) Assignments- The statements giving values to variables are called assignments.
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c) Declarations - Functions, classes in python are declared by using the keyword "def". The function declaration must end with semicolon ":"
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Indentation in Python- We need to leave spaces after every loops and function declarations. Brackets in Java are replaced by indentation in Python.
If Indentation is not respected, this error is generated.
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Moreover, every loop must end by a semicolon ':'

Comments in Python - Comments in Python begin with a '#' These commands are ignored by the interpreter and used to make the program clearer for the developers.

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Comments are an essential part of documentation. Proper documentation is a good programming habit. More about it here.


Now, let us see a sample Python program-

print("Program to accept student details.") 
#here, print() takes one string argument.

#input()  takes one string argument which it prints out.
#input()  returns one string argument
Rollno=int(input("Enter Roll Number ")) 
#int() converts the string into an integer type

name=input("Please enter a name ")

avg=float(input("enter percentage scored "))
#float() converts the string into an float type

print("Rollno of the student ",Rollno)
print("Name of the student ",name)
print("Percentage scored",avg,"%")
#here print() takes multiple arguments which it prints in the sequential order

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Output-
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Note, that as we need to operate upon the numbers inputted, we have used the int() method.
But if we input a character or string in place of the int, we will get the following error.
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In order to prevent such errors, error handling must be dont, which will be covered in this course...

Here is another program which gives the value of net resistance in parallel

a=int(input("Please enter first resistance "))
b=int(input("Please enter second resistance "))
c=(a*b)/(a+b)
#write the brackets carefully
print("answer is",c)
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output-image
More about operators in Python will be in the next blog...

Exercise----
1) Write a code in Python to find average of four numbers in one line, without declaring any variables.
2) Write a code to reverse a three digit number in Python.
(Answers can be found here)

To be continued....😏


So friends that's all for this part. 😊 Hope you all are enjoying.😎 Please let me know in the comment section if you liked it or not. 🧐 And don't forget to like the post if you did. 😍 I am open to any suggestions or doubts. 🤠 Just post in the comments below or gmail me. 😉
Thank you for being so patient.👍

Discussion (1)

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ahlam profile image
ahlam-design

Clear and to the point 👏🏿