1
00:00:00,150 --> 00:00:03,840
Before we start, did you try solving the workbook yourself?

2
00:00:03,870 --> 00:00:09,630
If not, please click the link in the resources folder and follow the instructions for this workbook.

3
00:00:10,980 --> 00:00:12,570
Welcome to Work Book 4.3.

4
00:00:12,570 --> 00:00:15,090
Let us jump right into it.

5
00:00:15,120 --> 00:00:21,540
Task one is to make a function called Fahrenheit two Celsius that expects to receive a double value.

6
00:00:21,540 --> 00:00:27,210
And then from the value that it receives, it's going to return a Celsius result.

7
00:00:27,210 --> 00:00:30,930
So I will start by defining my function over here.

8
00:00:30,960 --> 00:00:32,460
Public static.

9
00:00:32,460 --> 00:00:38,700
The functions return type needs to be double because we expect to return a double value and the function

10
00:00:38,700 --> 00:00:40,860
name is Fahrenheit to Celsius.

11
00:00:40,860 --> 00:00:48,390
The function must define one parameter called Fahrenheit because ultimately we're going to be receiving

12
00:00:48,390 --> 00:00:52,320
a Fahrenheit temperature and then converting it to Celsius.

13
00:00:52,320 --> 00:00:53,370
How will we do that?

14
00:00:53,400 --> 00:00:56,580
We're going to do that using the formula that was provided.

15
00:00:56,580 --> 00:00:58,200
So we'll say return.

16
00:01:02,220 --> 00:01:07,440
Copying the following Replace F with the Fahrenheit temperature that gets passed in.

17
00:01:07,980 --> 00:01:08,850
And that is all.

18
00:01:08,850 --> 00:01:15,210
When this function gets called, it will receive a Fahrenheit value, and the result that we return

19
00:01:15,210 --> 00:01:19,860
will be the conversion from Fahrenheit to Celsius using the following formula.

20
00:01:22,720 --> 00:01:25,750
Let's call this function three separate times.

21
00:01:26,750 --> 00:01:29,640
One four, the temperature in Fahrenheit at midnight.

22
00:01:29,660 --> 00:01:33,170
One for the temperature in Fahrenheit and during the evening.

23
00:01:33,290 --> 00:01:35,150
And one during noon.

24
00:01:40,910 --> 00:01:41,360
All right.

25
00:01:41,360 --> 00:01:47,120
Let us step inside the function every time we call it first, we're calling it passing in a value of

26
00:01:47,120 --> 00:01:49,100
77 degrees Fahrenheit.

27
00:01:49,160 --> 00:01:54,590
If you step inside the function, the Fahrenheit parameter stores the value that was passed in.

28
00:01:54,590 --> 00:01:59,960
And here, using the value that was passed in, we can calculate what the corresponding Celsius temperature

29
00:01:59,960 --> 00:02:02,570
will be and return the final result.

30
00:02:04,080 --> 00:02:08,490
The function call retains the return value of 25 degrees.

31
00:02:09,000 --> 00:02:10,919
But we're not really doing anything with it.

32
00:02:10,919 --> 00:02:16,740
So moving on to the next breakpoint here, we're calling the function again, this time passing in a

33
00:02:16,740 --> 00:02:19,320
temperature of 61 degrees Fahrenheit.

34
00:02:20,040 --> 00:02:23,340
The parameter stores, the value that was passed in.

35
00:02:23,340 --> 00:02:29,310
And here, using the Fahrenheit temperature, we can calculate the corresponding Celsius temperature

36
00:02:29,310 --> 00:02:30,420
and return it.

37
00:02:30,420 --> 00:02:37,410
And the function call holds on to the return value of 16.11 degrees Celsius.

38
00:02:37,410 --> 00:02:43,950
We could store it in a variable, but right now let us just move on to task number two and stop the

39
00:02:43,960 --> 00:02:44,730
runtime.

40
00:02:45,060 --> 00:02:49,890
Okay, So we've successfully defined our Fahrenheit to Celsius function.

41
00:02:50,430 --> 00:02:51,750
That's it for task one.

42
00:02:52,020 --> 00:02:56,700
Task number two is to make a function that prints all of the temperatures.

43
00:02:56,700 --> 00:03:01,200
It's going to need to receive a Fahrenheit temperature and it will not return anything.

44
00:03:01,200 --> 00:03:05,190
So right there, we know that it's going to be void, public static void.

45
00:03:05,190 --> 00:03:10,410
The function will not return anything because all it will do is print a bunch of temperatures.

46
00:03:10,410 --> 00:03:13,320
It's going to receive the Fahrenheit temperature.

47
00:03:14,900 --> 00:03:19,580
And upon receiving a Fahrenheit value, the first thing that we're going to do is print it.

48
00:03:19,580 --> 00:03:23,330
So we'll say the value in Fahrenheit equals.

49
00:03:25,640 --> 00:03:27,380
Whatever value that was passed in.

50
00:03:28,240 --> 00:03:33,430
And the second print statement is going to calculate the corresponding Celsius temperature.

51
00:03:37,430 --> 00:03:44,690
So here what we can do is call Fahrenheit to Celsius, and then at the end we will print a new line.

52
00:03:45,350 --> 00:03:49,580
So what this line is doing is printing a double value.

53
00:03:49,580 --> 00:03:55,850
And what this line is doing is printing whatever double value gets returned when we call Fahrenheit

54
00:03:55,880 --> 00:03:57,020
to Celsius.

55
00:03:58,340 --> 00:03:59,300
All right.

56
00:03:59,450 --> 00:04:03,320
Now, what I'm going to do is call print temperatures.

57
00:04:07,180 --> 00:04:08,890
And now we can visualize the runtime.

58
00:04:11,460 --> 00:04:16,829
So here we're calling print temperatures, passing in a temperature of 77 degrees Fahrenheit.

59
00:04:16,860 --> 00:04:20,490
Here we're just printing the Fahrenheit value that was passed in.

60
00:04:21,029 --> 00:04:22,830
And here we're calling to functions.

61
00:04:22,830 --> 00:04:26,870
We're calling the print line function, and we're calling Fahrenheit to Celsius.

62
00:04:26,880 --> 00:04:31,020
So the first step into is going to take you to some random class.

63
00:04:31,020 --> 00:04:32,820
We'll step out of it.

64
00:04:32,820 --> 00:04:38,970
And then the next step into is going to step inside of our second function call Fahrenheit to Celsius.

65
00:04:38,970 --> 00:04:44,730
And based on the value that was passed in, we're calculating the corresponding Celsius temperature

66
00:04:44,730 --> 00:04:47,040
and we're returning the final result.

67
00:04:47,070 --> 00:04:50,340
The function call basically equals the return value.

68
00:04:50,370 --> 00:04:55,710
It equals the final result of 25 degrees Celsius, which we are then printing.

69
00:04:57,720 --> 00:04:58,260
All right.

70
00:04:58,260 --> 00:05:00,330
Continuing to the next breakpoint here.

71
00:05:00,330 --> 00:05:02,180
We're calling the function a second time.

72
00:05:02,190 --> 00:05:05,610
This time we're passing in a value of 61 degrees Fahrenheit.

73
00:05:05,910 --> 00:05:08,550
Here we're just printing the value that was passed in.

74
00:05:08,550 --> 00:05:12,270
But then here we're printing whatever, Fahrenheit to Celsius returns.

75
00:05:12,270 --> 00:05:16,590
In this case, it's going to return 16.21 degrees Celsius.

76
00:05:16,620 --> 00:05:22,260
Now, I'm just going to continue to the next breakpoint, keep pressing, continue this time calling

77
00:05:22,260 --> 00:05:26,300
print temperatures for a Fahrenheit value of 55 degrees.

78
00:05:26,310 --> 00:05:30,870
In this case, it's going to rent a Celsius value of 12.7 degrees.

79
00:05:31,230 --> 00:05:31,830
That is all.

80
00:05:31,830 --> 00:05:34,380
I hope you enjoyed this breakpoint session.