Difference between revisions of "Java/C2/Logical-Operations/English-timed"

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{| border=1
 
{| border=1
|| ''Time'''
+
|| '''Time'''
 
|| '''Narration'''
 
|| '''Narration'''
 +
 
|-
 
|-
 
| 00:02
 
| 00:02
Line 8: Line 9:
 
|-
 
|-
 
| 00:07
 
| 00:07
|  In this tutorial, you will learn about the''' logical operators   
+
|  In this tutorial, you will learn about the '''logical operators'''.  
  
 
|-
 
|-
 
| 00:11
 
| 00:11
| '''how to check for multiple expressions using logical operators''' and '''how to override precedence using parentheses'''
+
|How to check for multiple '''expressions''' using '''logical operators''' and how to '''override''' '''precedence''' using parentheses.
  
 
|-
 
|-
 
| 00:20
 
| 00:20
| For this tutorial we are using  
+
| For this tutorial we are using:
  
 
'''Ubuntu 11.10''',  
 
'''Ubuntu 11.10''',  
Line 26: Line 27:
 
|-
 
|-
 
| 00:30
 
| 00:30
|  To follow this tutorial you should have knowledge on '''relational operators in Java'''
+
|  To follow this tutorial, you should have knowledge on '''relational operators''' in Java.
  
 
|-
 
|-
Line 33: Line 34:
  
 
|-
 
|-
| 00:40
+
| 00:42
| Logical operators are used to check '''multiple conditions'''.  
+
| Logical operators are used to check for '''multiple conditions'''.  
  
 
|-
 
|-
 
| 00:48
 
| 00:48
| Here is a list of the available logical operators in Java
+
| Here is a list of the available '''logical operators''' in Java.
  
 
|-
 
|-
 
| 00:54
 
| 00:54
| and, or, not. We shall look into each of them in detail. Switch to Eclipse.
+
| '''and, or, not'''. We shall look into each of them in detail. Switch to '''Eclipse'''.
  
 
|-
 
|-
 
| 01:04
 
| 01:04
|  Here We have the Eclipse IDE and  the skeleton required for the rest of the code.
+
|  Here, we have the 'Eclipse IDE' and  the skeleton required for the rest of the code.
  
 
|-
 
|-
 
| 01:10
 
| 01:10
| We have created a class '''LogicalOperators''' and added the main method  
+
| We have created a '''class''' '''LogicalOperators''' and added the '''main method'''.
  
 
|-
 
|-
 
|01:15  
 
|01:15  
| Let us create some variables.
+
| Let us '''create''' some '''variables'''.
  
 
|-
 
|-
 
|  01:20
 
|  01:20
|  '''boolean b ; '''
+
|  '''boolean b ;'''
 +
 
 
|-
 
|-
 
| 01:23
 
| 01:23
| We shall store the result of conditions in b;
+
| We shall store the result of conditions in 'b';
  
 
|-
 
|-
 
| 01:29
 
| 01:29
|   '''''int age''' is equalto '''11 '''  
+
| '''int age''' is equal to 11;  
  
 
|-
 
|-
 
| 01:35
 
| 01:35
| '''''int weight '''isequalto '''42 '''
+
| '''int weight''' is equal to 42;
 
   
 
   
 
 
|-
 
|-
 
|  01:42
 
|  01:42
Line 78: Line 79:
 
|-
 
|-
 
| 01:46
 
| 01:46
| We shall check if the person '''is below 18yrs of age and is atleast 40kgs'''.
+
| We shall check if the person is below 18yrs of age and is at least 40kgs.
 
+
  
 
|-
 
|-
Line 87: Line 87:
 
|-
 
|-
 
|  01:57
 
|  01:57
| '''b''' is equal to'''age''' ''less than '''''18''' ''ampersand ampersand'' '''weight''' ''greater than equal to'' '''40'''
+
| '''b''' is equal to '''age''' less than '''18''' ampersand ampersand '''weight''' greater than equal to '''40''';
 
+
  
 
|-
 
|-
 
| 02:19
 
| 02:19
| This statement has two expressions and a double ampersand symbol in between.  
+
| This statement has two '''expressions''' and a double ampersand symbol in between.  
 
+
  
 
|-
 
|-
 
| 02:24
 
| 02:24
| It checks if age is less than 18 and also if weight is greater than or equal to 40.
+
| It checks if '''age''' is less than '''18''' and also if '''weight''' is greater than or equal to '''40'''.
 
+
  
 
|-
 
|-
Line 106: Line 103:
 
|-
 
|-
 
|  02:35
 
|  02:35
|  Let us now print the value b.
+
|  Let us now print the value of 'b'.  
 
+
  
 
|-
 
|-
 
| 02:40
 
| 02:40
| '''''System '''dot '''out '''dot '''println(''b'');'''''
+
| '''System''' dot '''out''' dot '''println(b);'''
  
 
|-
 
|-
 
| 02:48
 
| 02:48
|'''Save '''and '''Run '''  
+
|'''Save '''and '''Run '''.
  
 
|-
 
|-
 
| 02:56
 
| 02:56
 
|  As we can see, the output is '''true''' because both the conditions are satisfied.
 
|  As we can see, the output is '''true''' because both the conditions are satisfied.
 
  
 
|-
 
|-
 
| 03:02
 
| 03:02
| Now let us change the weight so that one condition is not satisfied and re run the code.
+
| Now, let us change the '''weight''' so that one condition is not satisfied and ''re-run'' the code.
 
+
  
 
|-
 
|-
 
| 03:08
 
| 03:08
 
| Change '''42''' to '''32.'''
 
| Change '''42''' to '''32.'''
 
  
 
|-
 
|-
 
| 03:14
 
| 03:14
| '''Save''' and '''Run'''   
+
| '''Save''' and '''Run'''.  
  
 
|-
 
|-
 
|  03:21
 
|  03:21
the output now is false.
+
The output now is '''false.'''
 
+
  
 
|-
 
|-
 
| 03:24
 
| 03:24
| This is because the condition age   less than 18 is  satisfied
+
| This is because the condition '''age''' less than '''18''' is  satisfied
 
+
  
 
|-
 
|-
 
| 03:29
 
| 03:29
| But the condition the weight   greater than or equal to 40 is not satisfied
+
| but the condition '''weight'''  greater than or equal to '''40''' is not satisfied.
 
+
  
 
|-
 
|-
 
| 03:34
 
| 03:34
| The '''and''' operation requires both the conditions to be '''true''' for the result to be true.
+
| The '''AND''' operation requires both the conditions to be '''true''' for the result to be '''true.'''
 
+
  
 
|-
 
|-
 
| 03:39
 
| 03:39
| Therefore we get false as our output.
+
| Therefore we get '''false''' as our output.
  
 
|-
 
|-
 
| 03:43
 
| 03:43
| This way, using a  double ampersand symbol we can perform  '''and''' operation.
+
| This way, using a  double ampersand symbol we can perform  an '''AND''' operation.
 
   
 
   
 
|-
 
|-
 
|  03:53
 
|  03:53
| Lets say we have age and weight and it is enough if only one of the conditions is satisfied.
+
| Let's say we have '''age''' and '''weight''' and it is enough if only one of the conditions is satisfied.
 
+
  
 
|-
 
|-
 
| 03:59
 
| 03:59
| In other words, we need to see if the first condition '''or''' the second condition is '''true.'''
+
| In other words, we need to see if the first condition or the second condition is '''true.'''
 
+
  
 
|-
 
|-
 
| 04:05
 
| 04:05
| It is done using the '''or''' operation.
+
| It is done using the '''OR''' operation.
  
 
|-
 
|-
 
|  04:09
 
|  04:09
 
|  Let us first remove the earlier condition.
 
|  Let us first remove the earlier condition.
 
  
 
|-
 
|-
 
| 04:15
 
| 04:15
| And  Type
+
| And  type:
 
+
  
 
|-
 
|-
 
| 04:17
 
| 04:17
| '''age''' ''less than equal to'' '''15''' ''pipe pipe'' '''weight''' ''less than equal to '''''30'''
+
| '''age''' less than or equal to '''15''' pipe pipe '''weight''' less than or equal to '''30'''
 
+
  
 
|-
 
|-
 
| 04:35
 
| 04:35
| There are two conditions and a double pipe symbol in between.
+
| There are two conditions and a '''double pipe''' symbol in between.
 
+
  
 
|-
 
|-
 
| 04:40
 
| 04:40
| This statement checks if atleast one of the given two conditions is satisfied.
+
| This statement checks if at least one of the given two conditions is satisfied.
 
+
  
 
|-
 
|-
 
| 04:46
 
| 04:46
| Let us run the code to see the output. Save and run
+
| Let us run the code to see the output. '''Save''' and '''run'''.
  
 
|-
 
|-
 
| 04:54
 
| 04:54
|  We see that the output is True.
+
|  We see that the output is '''true.'''
  
 
|-
 
|-
 
|  04:57  
 
|  04:57  
|  This is because, an '''or''' operation, does not need both the conditions to be true like the and operation.
+
|  This is because an '''OR''' operation does not need both the conditions to be true like the '''AND''' operation.
  
 
|-
 
|-
 
|  05:03
 
|  05:03
|  It needs atleast one condition to be true.
+
|  It needs at least one condition to be '''true.'''
  
 
|-
 
|-
 
| 05:06
 
| 05:06
|   So although the condition for weight is not satisfied, since the condition for age is satisfied.
+
| So, although the condition for '''weight''' is not satisfied, since the condition for '''age''' is satisfied
  
 
|-
 
|-
 
| 05:13
 
| 05:13
|   we get the output as true.
+
| we get the output as '''true.'''
  
 
|-
 
|-
 
| 05:18
 
| 05:18
|  Now let us change the age in  such a way that both the conditions are false and see the result.
+
|  Now, let us change the '''age''' in  such a way that both the conditions are false and see the result.
 
+
 
   
 
   
 
|-
 
|-
 
| 05:25
 
| 05:25
|  change '''11''' to '''17'''
+
|  change '''11''' to '''17'''.
 
+
  
 
|-
 
|-
 
| 05:30
 
| 05:30
| '''Save''' and '''Run '''  
+
| '''Save''' and '''Run '''.
  
 
|-
 
|-
 
| 05:36
 
| 05:36
| Now the output is false because both the conditions are not satisfied.
+
| Now the output is '''false''' because both the conditions are not satisfied.
  
 
|-
 
|-
 
|  05:41  
 
|  05:41  
|  This way, we use a double PIPE symbol to do an '''or''' operation.
+
|  This way, we use a double PIPE symbol to do an '''OR''' operation.
  
 
|-
 
|-
 
| 05:50
 
| 05:50
|  Now let us say we need to check for people who are older than 15 and with weight more than 30kilos.
+
|  Now, let us say we need to check for people who are older than 15 and with weight more than 30kilos.
 
+
  
 
|-
 
|-
Line 260: Line 239:
 
|-
 
|-
 
| 06:03
 
| 06:03
| In such situations, we use the '''not''' operation
+
| In such situations, we use the '''NOT''' operation.
  
 
|-
 
|-
 
|  06:07
 
|  06:07
|  First enclose the condition in parentheses.
+
|  First, enclose the condition in parentheses.
  
 
|-
 
|-
 
|  06:17
 
|  06:17
|  And  Add an exclamation mark before the condition.
+
|  And  add an exclamation mark before the condition.
  
 
|-
 
|-
 
| 06:25
 
| 06:25
 
|  By using an exclamation mark, we check for the exact opposite of the condition inside the parentheses.
 
|  By using an exclamation mark, we check for the exact opposite of the condition inside the parentheses.
 
 
  
 
|-
 
|-
 
|  06:32
 
|  06:32
|  Since the earlier output was '''false''', now it must  '''true'''. Let us see
+
|  Since the earlier output was '''false''', now it must be   '''true'''. Let us see.
  
 
|-
 
|-
 
|  06:38
 
|  06:38
 
|  '''Save''' and '''Run'''.  
 
|  '''Save''' and '''Run'''.  
 
  
 
|-
 
|-
Line 291: Line 267:
 
|-
 
|-
 
| 06:48  
 
| 06:48  
|  This way by using the''' Exclamation mark''' we perform '''not''' operation. Now Let us say we want people '''younger than 15.'''
+
|  This way, by using the exclamation mark we perform the '''NOT''' operation. Now, let us say we want people younger than 15.
  
 
|-
 
|-
 
| 06:58
 
| 06:58
| Or people '''younger than 18''' and '''lighter than 40kilos'''.
+
| Or people younger than 18 and lighter than 40kilos.
 
+
  
 
|-
 
|-
Line 304: Line 279:
 
|-
 
|-
 
| 07:07
 
| 07:07
|  Remove the earlier condition and type   
+
|  Remove the earlier condition and type:  
  
 
|-
 
|-
 
| 07:12  
 
| 07:12  
| '''age '''''less than '''''15 '''
+
| '''age''' less than '''15'''
  
 
|-
 
|-
 
| 07:15
 
| 07:15
| ''or''''' age '''''less than '''''18 '''
+
| '''OR''' '''age''' less than '''18 '''
  
 
|-
 
|-
 
| 07:24
 
| 07:24
| ''and''''' weight '''''less than '''''40'''
+
| '''AND''' '''weight''' less than '''40''';
 
+
  
 
|-
 
|-
 
| 07:33
 
| 07:33
 
| As we can see, the condition itself is confusing.
 
| As we can see, the condition itself is confusing.
 
  
 
|-
 
|-
 
| 07:36
 
| 07:36
| Moreover, we do not know if the '''or''' operation will be performed first or the '''and''' operation.
+
| Moreover, we do not know if the '''OR''' operation will be performed first or the '''AND''' operation.
 
+
  
 
|-
 
|-
 
|  07:42
 
|  07:42
| It depends on the precedence of operators.
+
| It depends on the precedence of '''operators'''.
 
+
  
 
|-
 
|-
Line 340: Line 311:
 
|-
 
|-
 
| 07:53
 
| 07:53
|   So let us add the parentheses.  
+
| So let us add the parentheses.  
 
+
 
+
 
   
 
   
 
|-
 
|-
 
|  08:06
 
|  08:06
| Let us run the code save run   
+
| Let us '''run''' the code,  '''save''', '''run'''.  
 +
 
 
|-
 
|-
 
| 08:13
 
| 08:13
| Now Although the first condition which is age less than 15 is not satisfied,
+
| Now, although the first condition which is '''age''' less than 15 is not satisfied,
 
+
  
 
|-
 
|-
 
| 08:20
 
| 08:20
|  the second condition, which is,
+
|  the second condition which is
 
+
  
 
|-
 
|-
 
| 08:22
 
| 08:22
| age less than 18 and weight less than 40 is satisfied.
+
| '''age''' less than 18 and '''weight''' less than 40 is satisfied.
 
+
  
 
|-
 
|-
 
| 08:27
 
| 08:27
| Therefore, output is True.
+
| Therefore, the output is '''true'''.
  
 
|-
 
|-
 
|  08:30
 
|  08:30
| As a rule, use parentheses to avoid ambiguity and make the expressions clear.
+
| As a rule, use parentheses to avoid ambiguity and make the '''expressions''' clear.
  
 
|-
 
|-
 
|  08:36
 
|  08:36
|  | And  This how we use the logical operators to check for multiple conditions.
+
|  | And  this is how we use the logical operators to check for multiple conditions.
  
 
|-
 
|-
 
| 08:44
 
| 08:44
|  This bring us to the end of this tutorial.  
+
|  This brings us to the end of the tutorial.  
  
 
|-
 
|-
 
| 08:47
 
| 08:47
we have learnt '''about logical operators''', how to '''check for multiple expressions''' using '''logical operators '''and  
+
We have learnt about '''logical operators''', how to check for multiple '''expressions''' using '''logical operators '''and  
  
 
|-
 
|-
 
| 08:54
 
| 08:54
| '''how to override the precedence using parentheses.'''
+
| how to '''override''' the precedence using parentheses.
  
 
|-
 
|-
 
|09:00
 
|09:00
 
|As an assignment for this tutorial,  
 
|As an assignment for this tutorial,  
 
  
 
|-
 
|-
 
| 09:02
 
| 09:02
| find out if the two expressions, shown are equivalent?
+
| find out if the two expressions shown are equivalent?
  
 
|-
 
|-
 
|  09:10
 
|  09:10
| To know more about the '''Spoken Tutorial''' project, watch the video available at the following linkIt summarises the '''Spoken Tutorial'''project.
+
| To know more about the Spoken Tutorial project, watch the video available at the following link. It summarizes the Spoken Tutorial project.
  
 
|-
 
|-
 
| 09:18
 
| 09:18
| if you do not have good bandwidth, you can download and watch it
+
| If you do not have good bandwidth, you can download and watch it.
  
 
|-
 
|-
 
|  09:23
 
|  09:23
|  The Spoken Tutorial Project Team. Conducts workshops using '''spoken tutorials''' and gives certificates for those who pass an online test.  
+
|  The Spoken Tutorial Project Team: Conducts workshops using spoken tutorials and gives certificates to those who pass an online test.  
  
 
|-
 
|-
Line 413: Line 379:
 
|-
 
|-
 
|  09:36
 
|  09:36
| '''Spoken Tutorial '''Project is a part of the '''Talk to a Teacher''' project  
+
| Spoken Tutorial Project is a part of the 'Talk to a Teacher' project.
 
|-
 
|-
 
| 09:40
 
| 09:40
|  It is supported by the '''National Mission on Education through ICT, MHRD, Government of India.  
+
|  It is supported by the National Mission on Education through ICT, MHRD, Government of India.  
 
|-
 
|-
 
| 09:46
 
| 09:46
| '''More information on this Mission is available at the following link '''spoken HYPHEN tutorial DOT org SLASH NMEICT HYPHEN Intro'''
+
| More information on this mission is available at the following link: '''spoken HYPHEN tutorial DOT org SLASH NMEICT HYPHEN Intro'''.
  
 
|-
 
|-
 
|  09:52
 
|  09:52
 
|This tutorial has been contributed by '''TalentSprint'''. Thanks for joining.
 
|This tutorial has been contributed by '''TalentSprint'''. Thanks for joining.
 
 
 
  
 
|}
 
|}

Latest revision as of 23:47, 5 April 2015

Time Narration
00:02 Welcome to this spoken tutorial on Logical Operators in Java.
00:07 In this tutorial, you will learn about the logical operators.
00:11 How to check for multiple expressions using logical operators and how to override precedence using parentheses.
00:20 For this tutorial we are using:

Ubuntu 11.10,

JDK 1.6 and

Eclipse 3.7

00:30 To follow this tutorial, you should have knowledge on relational operators in Java.
00:35 If not, for relevant tutorials, please visit our website as shown.
00:42 Logical operators are used to check for multiple conditions.
00:48 Here is a list of the available logical operators in Java.
00:54 and, or, not. We shall look into each of them in detail. Switch to Eclipse.
01:04 Here, we have the 'Eclipse IDE' and the skeleton required for the rest of the code.
01:10 We have created a class LogicalOperators and added the main method.
01:15 Let us create some variables.
01:20 boolean b ;
01:23 We shall store the result of conditions in 'b';
01:29 int age is equal to 11;
01:35 int weight is equal to 42;
01:42 We have the age and weight of a person.
01:46 We shall check if the person is below 18yrs of age and is at least 40kgs.
01:52 Let us see how to do so.
01:57 b is equal to age less than 18 ampersand ampersand weight greater than equal to 40;
02:19 This statement has two expressions and a double ampersand symbol in between.
02:24 It checks if age is less than 18 and also if weight is greater than or equal to 40.
02:31 This operation is called the and operation.
02:35 Let us now print the value of 'b'.
02:40 System dot out dot println(b);
02:48 Save and Run .
02:56 As we can see, the output is true because both the conditions are satisfied.
03:02 Now, let us change the weight so that one condition is not satisfied and re-run the code.
03:08 Change 42 to 32.
03:14 Save and Run.
03:21 The output now is false.
03:24 This is because the condition age less than 18 is satisfied
03:29 but the condition weight greater than or equal to 40 is not satisfied.
03:34 The AND operation requires both the conditions to be true for the result to be true.
03:39 Therefore we get false as our output.
03:43 This way, using a double ampersand symbol we can perform an AND operation.
03:53 Let's say we have age and weight and it is enough if only one of the conditions is satisfied.
03:59 In other words, we need to see if the first condition or the second condition is true.
04:05 It is done using the OR operation.
04:09 Let us first remove the earlier condition.
04:15 And type:
04:17 age less than or equal to 15 pipe pipe weight less than or equal to 30
04:35 There are two conditions and a double pipe symbol in between.
04:40 This statement checks if at least one of the given two conditions is satisfied.
04:46 Let us run the code to see the output. Save and run.
04:54 We see that the output is true.
04:57 This is because an OR operation does not need both the conditions to be true like the AND operation.
05:03 It needs at least one condition to be true.
05:06 So, although the condition for weight is not satisfied, since the condition for age is satisfied
05:13 we get the output as true.
05:18 Now, let us change the age in such a way that both the conditions are false and see the result.
05:25 change 11 to 17.
05:30 Save and Run .
05:36 Now the output is false because both the conditions are not satisfied.
05:41 This way, we use a double PIPE symbol to do an OR operation.
05:50 Now, let us say we need to check for people who are older than 15 and with weight more than 30kilos.
05:57 In other words, we need to check the exact opposite of the condition we just did.
06:03 In such situations, we use the NOT operation.
06:07 First, enclose the condition in parentheses.
06:17 And add an exclamation mark before the condition.
06:25 By using an exclamation mark, we check for the exact opposite of the condition inside the parentheses.
06:32 Since the earlier output was false, now it must be true. Let us see.
06:38 Save and Run.
06:44 As we can see, the output is the opposite of earlier one.
06:48 This way, by using the exclamation mark we perform the NOT operation. Now, let us say we want people younger than 15.
06:58 Or people younger than 18 and lighter than 40kilos.
07:04 Let us see how would we go about this condition.
07:07 Remove the earlier condition and type:
07:12 age less than 15
07:15 OR age less than 18
07:24 AND weight less than 40;
07:33 As we can see, the condition itself is confusing.
07:36 Moreover, we do not know if the OR operation will be performed first or the AND operation.
07:42 It depends on the precedence of operators.
07:46 In such situations, we use parentheses to overwrite the precedence and also make the condition clear.
07:53 So let us add the parentheses.
08:06 Let us run the code, save, run.
08:13 Now, although the first condition which is age less than 15 is not satisfied,
08:20 the second condition which is
08:22 age less than 18 and weight less than 40 is satisfied.
08:27 Therefore, the output is true.
08:30 As a rule, use parentheses to avoid ambiguity and make the expressions clear.
08:36 And this is how we use the logical operators to check for multiple conditions.
08:44 This brings us to the end of the tutorial.
08:47 We have learnt about logical operators, how to check for multiple expressions using logical operators and
08:54 how to override the precedence using parentheses.
09:00 As an assignment for this tutorial,
09:02 find out if the two expressions shown are equivalent?
09:10 To know more about the Spoken Tutorial project, watch the video available at the following link. It summarizes the Spoken Tutorial project.
09:18 If you do not have good bandwidth, you can download and watch it.
09:23 The Spoken Tutorial Project Team: Conducts workshops using spoken tutorials and gives certificates to those who pass an online test.
09:30 For more details, please write to contact AT spoken HYPHEN tutorial DOT org.
09:36 Spoken Tutorial Project is a part of the 'Talk to a Teacher' project.
09:40 It is supported by the National Mission on Education through ICT, MHRD, Government of India.
09:46 More information on this mission is available at the following link: spoken HYPHEN tutorial DOT org SLASH NMEICT HYPHEN Intro.
09:52 This tutorial has been contributed by TalentSprint. Thanks for joining.

Contributors and Content Editors

Gaurav, Kavita salve, PoojaMoolya, Priyacst, Sandhya.np14, Sneha