Would you like to inspect the original subtitles? These are the user uploaded subtitles that are being translated:
1
00:00:00,360 --> 00:00:04,200
Logical operators can join many comparisons into one condition.
2
00:00:05,840 --> 00:00:12,380
In the last lesson, you set up a series of if elsea final statements, notice that each condition only
3
00:00:12,380 --> 00:00:13,670
has one comparison.
4
00:00:15,450 --> 00:00:19,170
In this lesson, you're going to connect many comparisons into one condition.
5
00:00:21,130 --> 00:00:25,690
The first thing I'll need you to do is create a new class by yourself inside the Section three project,
6
00:00:25,690 --> 00:00:31,150
create a new file named Logical Operators Java, and make sure the class has a main method.
7
00:00:35,930 --> 00:00:39,260
With a logical operator, we can compare many things at once.
8
00:00:40,790 --> 00:00:44,240
And the most common logical operators are or and end.
9
00:00:45,490 --> 00:00:50,140
We're going to start with the owner operator and this one returns true if either comparison is true.
10
00:00:51,960 --> 00:00:54,250
And there are three parts to the owner operator.
11
00:00:54,630 --> 00:01:00,210
There's the first comparison, and then there's the owner operator represented by two vertical lines
12
00:01:00,630 --> 00:01:04,610
such that if any of the comparisons are true, the entire condition becomes true.
13
00:01:05,250 --> 00:01:07,020
And then there's the second comparison.
14
00:01:08,170 --> 00:01:11,020
So what are some use cases for the or operator?
15
00:01:12,430 --> 00:01:17,860
Well, think about this, you're applying for a scholarship and to get the scholarship you need above
16
00:01:17,860 --> 00:01:21,120
a seventy five in chemistry or in English.
17
00:01:21,820 --> 00:01:23,920
So we're going to make two integer variables.
18
00:01:23,920 --> 00:01:27,220
Chemistry grade set that equal to seventy eight.
19
00:01:29,520 --> 00:01:32,520
An English grade return is set equal to sixty five.
20
00:01:39,040 --> 00:01:43,510
Now we're going to make if statement where they condition and inside the condition, we're going to
21
00:01:43,510 --> 00:01:50,920
check if chemistry great is greater than 75, did they get above a 75 in chemistry or we'll check if
22
00:01:50,920 --> 00:01:53,380
English grade is bigger than 75.
23
00:02:06,260 --> 00:02:10,970
And if either one of these comparisons is true, the entire condition is going to be true, in which
24
00:02:10,970 --> 00:02:12,350
case we're going to print.
25
00:02:16,300 --> 00:02:17,500
Congratulations.
26
00:02:21,670 --> 00:02:23,290
You got the scholarship.
27
00:02:26,780 --> 00:02:28,220
Otherwise, we're going to print.
28
00:02:32,210 --> 00:02:33,620
You didn't get the scholarship.
29
00:02:43,110 --> 00:02:44,910
All right, I think we're ready to run our coat.
30
00:02:55,900 --> 00:02:58,870
And the condition is true, you did get the scholarship.
31
00:03:00,930 --> 00:03:06,780
The or operator checks, if one of the comparisons is true, only one of them has to be true, and the
32
00:03:06,780 --> 00:03:11,970
first comparison is to the entire condition is true and the code runs.
33
00:03:15,270 --> 00:03:18,180
Now we're going to change the students chemistry grade to 67.
34
00:03:21,270 --> 00:03:22,590
We're going to rerun the code.
35
00:03:26,450 --> 00:03:29,150
And this time the code inside Elsa runs.
36
00:03:31,360 --> 00:03:36,790
None of the comparisons are true, so the condition is false, so Jarvis skips over and runs the code
37
00:03:36,790 --> 00:03:37,800
inside ELT's.
38
00:03:42,340 --> 00:03:44,560
You can combine more than two comparisons.
39
00:03:45,850 --> 00:03:52,000
You can combine three comparisons into one condition for comparisons, five comparisons, as many as
40
00:03:52,000 --> 00:03:56,650
you want, as long as one of them is true, the entire condition is going to be true.
41
00:03:57,750 --> 00:04:00,780
And so back in coat, let's say the school decided to be generous.
42
00:04:01,020 --> 00:04:03,600
They're also going to offer you a scholarship if you know Java.
43
00:04:04,170 --> 00:04:07,500
So we're going to make a string variable and set it equal to Java.
44
00:04:12,540 --> 00:04:17,130
And now we're going to add another comparison to the condition, it's going to check if the variable
45
00:04:17,130 --> 00:04:20,720
equals Java, does the student know the Java programming language?
46
00:04:23,910 --> 00:04:25,050
Rewriting our code.
47
00:04:31,740 --> 00:04:33,840
And we got our scholarship back.
48
00:04:35,990 --> 00:04:38,900
The or operator checks if one of the comparisons is true.
49
00:04:39,830 --> 00:04:41,100
First one is false.
50
00:04:41,150 --> 00:04:47,300
The second one is false, but the last one is true to the entire condition is true and the code inside
51
00:04:47,300 --> 00:04:47,960
runs.
52
00:04:52,860 --> 00:04:54,840
Now we're going to talk about the end operator.
53
00:04:58,980 --> 00:05:00,780
And there are three parts to it as well.
54
00:05:01,050 --> 00:05:06,960
There is the first comparison, there's the end operator, which is a pair of ampersands and the second
55
00:05:06,960 --> 00:05:07,590
comparison.
56
00:05:08,310 --> 00:05:13,130
And with the end operation, the condition is only true if every comparison is true.
57
00:05:13,920 --> 00:05:16,330
In this case, the first comparison is false.
58
00:05:16,350 --> 00:05:18,930
So the entire condition becomes false.
59
00:05:20,850 --> 00:05:23,160
So what are some use cases for the end operator?
60
00:05:23,700 --> 00:05:24,870
Well, think about this.
61
00:05:25,080 --> 00:05:31,590
To get your diploma, you need at least 40 credits and a minimum GPA of 2.0.
62
00:05:32,220 --> 00:05:33,890
Now, credits are whole numbers.
63
00:05:33,900 --> 00:05:38,820
So we're going to make it into variable credits and we're going to set that equal to fifty six.
64
00:05:39,360 --> 00:05:41,390
And GPA is a decimal measure.
65
00:05:41,400 --> 00:05:46,080
So we're going to make a double variable GPA and set it equal to three point two.
66
00:05:47,390 --> 00:05:49,050
Now we're going to make another statement.
67
00:05:49,190 --> 00:05:55,310
First, we're going to check if a student has at least 40 credits, credits greater than or equal to
68
00:05:55,310 --> 00:06:01,100
40 and will check if they have a GPA of at least two point zero.
69
00:06:07,180 --> 00:06:12,400
And if the student satisfies both requirements, if both of these comparisons are true, we're going
70
00:06:12,400 --> 00:06:14,710
to print you earned your diploma.
71
00:06:26,880 --> 00:06:31,920
We're sorry, you need at least 40 credits and a minimum GPA of 2.0.
72
00:06:41,460 --> 00:06:43,050
All right, we're ready to run our code.
73
00:06:46,200 --> 00:06:51,630
The condition is indeed true, they got their diploma, the end operator checks, if every comparison
74
00:06:51,630 --> 00:06:56,370
is true, the student has about 40 credits and has a high enough GPA.
75
00:06:56,790 --> 00:06:59,880
So the entire condition is true and the coda runs.
76
00:07:04,370 --> 00:07:07,430
What if we change the students GPA to one point for.
77
00:07:08,450 --> 00:07:09,620
Rewriting our code.
78
00:07:14,330 --> 00:07:15,940
This time, they don't get their diploma.
79
00:07:19,250 --> 00:07:22,050
The end operator needs both comparisons to be true.
80
00:07:22,550 --> 00:07:28,890
The student has more than 40 credits, but there is too low, so the condition is false in the code
81
00:07:28,930 --> 00:07:29,480
runs.
82
00:07:33,480 --> 00:07:36,600
In this lesson, you connected many comparisons to one condition.
83
00:07:38,280 --> 00:07:44,340
The owner operator returns true if either comparison is true now, a student had a seven eight in chemistry
84
00:07:44,340 --> 00:07:49,830
and a sixty five in English, and you made a condition that checks if chemistry grade is greater than
85
00:07:49,830 --> 00:07:54,650
75 or in English, and the first comparison is true.
86
00:07:54,930 --> 00:07:58,860
And whether or not the second one is false or true, it doesn't matter.
87
00:07:59,010 --> 00:08:03,210
The entire condition becomes true and the code inside runs.
88
00:08:05,600 --> 00:08:11,360
Now, the end operator is different, it only returns true if every comparison, if every expression
89
00:08:11,360 --> 00:08:11,780
is true.
90
00:08:13,250 --> 00:08:19,790
Now, a student had 56 credits, but a GPA of one point four and you made a condition that checks if
91
00:08:19,790 --> 00:08:24,650
a student scored above 40 credits and had a minimum GPA of 2.0.
92
00:08:25,810 --> 00:08:29,950
The end operator needs both comparisons to be true, but one of them is false.
93
00:08:30,490 --> 00:08:36,039
This means that the entire condition is false and Java skips over to the L statements.
9211
Can't find what you're looking for?
Get subtitles in any language from opensubtitles.com, and translate them here.