Python-3.4.3/C3/Conditional-Statements/English-timed

Time	Narration
00:01	Welcome to the spoken tutorial on Conditional statements.
00:06	In this tutorial, we will learn to use if/else blocks
00:13	if/elif/else blocks Ternary conditional statement and Pass statement
00:22	To record this tutorial, I am using Ubuntu Linux 16.04 operating system
00:30	Python 3.4.3 and IPython 5.1.0
00:37	To practice this tutorial, you should know how to use basic data types and operators
00:46	strings and Input/Output statements
00:50	If not, see the relevant Python tutorials on this website.
00:55	First let us learn about if condition.
00:59	if condition is used to decide whether to execute the statements inside the if block or not. Here is the syntax.
01:10	Next we will see about if else condition.
01:14	When the test condition is true, it will execute the body of if.
01:20	If the condition is False, body of the else is executed.
01:25	Note that, if and else statements end with a colon.
01:30	This denotes the beginning of the code block of True or False condition.
01:36	All the statements inside a code block are indented by 4 spaces.
01:42	Let us start ipython. Open the terminal.
01:48	Type ipython3 and press Enter.
01:53	From here onwards, remember to press the Enter key after typing every command on the terminal.
02:00	Now let us check if an entered number is even or not.
02:05	Type, num is equal to int inside brackets input open and close brackets
02:14	Enter 4 and press Enter
02:18	Type, if num percentage 2 equal to equal to 0 colon
02:26	print inside brackets inside single quotes Even
02:32	Press backspace four times and type, else colon
02:39	print inside brackets inside single quotes Odd
02:44	Press Enter twice to get the output. As expected, it displays Even as output.
02:53	Note that, the statements inside a code block are indented by 4 spaces automatically.
03:00	Next we will see another conditional statement called elif.
03:05	All the syntax and rules for elif are same as if/else statements.
03:11	In if/else, only one condition is checked.
03:15	But in elif statement multiple conditions can be checked.
03:20	For example, The first block of code is executed as soon as condition one evaluates to True.
03:28	All the subsequent conditions in elif ladder are not checked.
03:33	The else block gets executed if all the conditions in if and elif ladder are evaluated to False.
03:42	Let us understand if/elif/else ladder with an example.
03:48	Type, a is equal to minus 3 We have a variable a which holds integer value as -3.
03:58	Type as shown. This program will print "positive" if a is positive,
04:06	"negative" if it is negative or "zero" if the above conditions are evaluated to False
04:15	Press Enter twice to see the output.
04:20	We can also have any number of elif conditions within an if/elif/else statements.
04:27	For example, based on the type of user the corresponding operations are performed using elif.
04:35	Pause the video. Try this exercise and then resume the video.
04:41	Given a number, num as input. Write an if else block to print num, if it is divisible by 10, else print 10 asterisk num.
04:53	The solution is on your screen.
04:57	Next let us learn about ternary operator.
05:01	Ternary operator allows to test a condition in a single line replacing the multiline if-else.
05:08	It can reduce the code size and increase the readability of the code. Here is the syntax.
05:16	Let us write a ternary conditional statement to find the largest of two numbers.
05:23	Type, a is equal to 4
05:26	b is equal to 2
05:30	large underscore num is equal to a if a greater than b else b
05:39	print inside brackets large underscore num
05:44	We got the required output.
05:47	Pause the video. Try this exercise and then resume the video.
05:53	Given a number, n as input. Write a ternary operator to print n, if it is divisible by 10, else print 10 asterisk n.
06:05	The solution is on your screen.
06:09	Next we will learn about pass statement.
06:13	The pass statement acts as a null operation (i.e) nothing happens when it executes.
06:21	It works as a placeholder for a block of code.
06:25	It is used in a code block where actual code implementation is not known yet.
06:32	Let us understand the pass statement with an example.
06:37	Type a is equal to 11
06:41	Then type as shown.
06:44	If a divided by 2 equals to zero, if block is executed. Else no operation is performed.
06:54	Press Enter key twice to get the output. Here a divided by 2 is not 0.
07:02	So no operation is performed and nothing is displayed as output.
07:08	This brings us to the end of the tutorial. Let us summarize.
07:14	In this tutorial, we have learnt the conditional statements such as, if/else statement
07:22	if/elif/else statement
07:25	Ternary conditional statement and Pass statement
07:30	Here are some self assessment questions for you to solve.
07:35	First. Given a variable t.
07:38	Print Good Morning if it is less than 12, otherwise print Hello. Use if else statement.
07:47	Second. Convert the below if else code into ternary conditional statement.
07:56	And the answers, First. The following code gives the required output.
08:03	Second. Use the following statement to convert the if else code into a ternary statement
08:11	Please post your timed queries in this forum.
08:15	Please post your general queries on Python in this forum.
08:20	FOSSEE team coordinates the TBC project.
08:24	Spoken Tutorial Project is funded by NMEICT, MHRD, Govt. of India. For more details, visit this website.
08:34	This is Priya from IIT Bombay signing off. Thanks for watching.

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