Python/C3/I-O/English-timed

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Time Narration
00:00 Hello friends and welcome to this tutorial on 'Input/Output'.
00:05 At the end of this tutorial,you will be able to,

Print some value. Print using modifiers. Take input from user. Display a prompt to the user before taking the input.

00:20 So type ipython in the terminal.
00:26 Type a = within double quotes This is a string

Type a Type print a

00:45 obviously, print a , prints the value of a .
00:52 As you can see, even when you type just a, the value of a is shown.
00:59 But there is a difference.
01:01 Typing just a displays the content of a whereas the statement print a prints the string itself.
01:08 This difference becomes more evident when we use strings with newlines in them.
01:14 Type b = within double quotes A line backslash n New line and hit enter

Type b Type print b

01:35 As you can see, just typing b shows that b contains a newline character but While typing print b,it prints the string and hence the newline.
01:46 Moreover when we type just a , the value a is shown only in interactive mode and does not have any effect on the program while running it as a script.
02:00 We shall look at different ways of outputting the data.
02:04 print statement in python supports string formatting.
02:08 Various arguments can be passed to print using modifiers.
02:12 type x = 1.5

y = 2 z = within double quotes red print then in double quotes x is modula 2 dot 1f comma y is modula d comma z is modula s then again a modula within brackets x comma y comma z


02:51 As you can see, the values of x, y and z are substituted in place of the modifiers modula 2.1f, modula d and modula s respectively.
03:03 Pause the video here, try out the following exercise and resume the video.
03:08 What happens when you do print within double quotes x is modula d comma y is modula f modula x comma y
03:19 Switch to the terminal for solution.
03:24 Type print within double quotes x is modula d comma y is modula f modula within brackets x comma y
03:50 We see that the int value of x and float value of y are printed corresponding to the modifiers used in the print statement.
03:58 We have seen that print statement prints a new line character every time it is called.
04:04 This can be suppressed by using a " comma " at the end of the print statement.
04:13 Let us see this by typing out following code on an editor as print underscore example.py
04:24 So Type..
04:44 print "Hello"

print "World" print "Hello" comma print "World"

05:22 Save the script as 'print underscore example.py' and run it using modula run slash home slash fossee slash print underscore example.py
05:34 As we can see, the print statement when used with comma in the end, prints a space instead of a new line.
05:46 Now we shall look at taking input from the user.
06:06 We will use the ~~raw underscore input~~ for this.
06:11 So type ip = raw underscore input()
06:23 The cursor is blinking indicating that it is waiting for input, so type something and hit enter.
06:32 So you can type an input
06:35 Now let us see what is the value of ip by typing it.
06:41 So type ip on the terminal and hit enter
06:45 We can see that it contains the string "an input"
06:51 Pause the video here, try out the following exercise and resume the video.
06:58 You have an question
07:02 Enter the number 5.6 as input and store it in a variable called c.
07:11 Switch to the terminal for solution.
07:15 We have to use the raw underscore input command with variable c.
07:19 So type c = raw underscore input() and hit enter

Put 5.6 And again enter. Type c

07:36 Now let us see the type of c.
07:40 Type type within brackets c
07:46 We see that c is a string.
07:49 This implies that anything you enter as input, it will be taken as a string no matter what you enter.
07:55 Pause the video here, try out the following exercise and resume the video.
07:59 What happens when you do not enter anything and hit enter.
08:04 Switch to the terminal for solution.
08:08 Type d = raw underscore input()

<RET> d

08:28 We see that when nothing is entered, an empty string is considered as input.
08:32 raw underscore input also can display a prompt to assist the user.
08:37 So type name = raw underscore input within brackets within double quotes Please enter your name:
08:48 It prints the string given as argument and then waits for the user input.
08:54 Let us do one more exercise.
08:56 Pause the video here, try out the following exercise and resume the video.
09:00 How do you display a prompt and let the user enter input in next line.
09:09 Switch to the terminal now.
09:12 The trick is to include a newline character at the end of the prompt string.
09:17 Type ip = raw underscore input within brackets within double quotes Please enter a number in the next line backslash n
09:28 It prints the newline character and hence the user enters input in the next line
09:35 This brings us to the end of the tutorial.
09:39 In this tutorial, we have learnt to, Use the print statement.
09:42 Use the modifiers modula d, modula f, modula s in the print statement.
09:47 Take input from user by using raw underscore input().
09:55 Display a prompt to the user before taking the input by passing a string as an argument to raw underscore input.
10:04 Here are some self assessment questions for you to solve
10:08 a = raw underscore input() and user enters 2.5 .
10:13 What is the type of a?

str int float char

10:20 2. a = 2 and b = 4.5.
10:27 What does ``print "a is modula d and b is In line literal start-string without end-string. modula 2.1f" modula within brackets b comma a`` print?

a is 2 and b is 4.5 a is 4 and b is 2 a is 4 and b is 2.0 a is 4.5 and b is 2

10:50 And the answers,
10:53 1.No matter what you enter, it will be taken as a string.
10:58 Hence 2.5 is a string.
11:01 Since 'b' is called first, It will display integer value of 'a' because the modifier used is modula d.
11:10 Similarly, 'b' will get the float value of 'a' due to it's modifier modula 2.1f.
11:18 Hence 'a' will be 4 and 'b' 2.0 .
11:24 Hope you have enjoyed this tutorial and found it useful.

Contributors and Content Editors

Gaurav, Minal, PoojaMoolya, Sneha