1 00:00:00,540 --> 00:00:11,790 Hello and welcome to this lecture or anything to be explaining what hashes are what is a hat in some 2 00:00:11,790 --> 00:00:17,150 programming languages it is referred to as a dictionary. 3 00:00:17,250 --> 00:00:20,240 Ruby Ruby just refers to it as the house. 4 00:00:20,350 --> 00:00:22,530 He has basically Ruby. 5 00:00:22,550 --> 00:00:28,980 He is an on ordered object index collection of objects. 6 00:00:29,310 --> 00:00:40,660 So in comparison two and three and three is an ordered collection of objects while a house is not ordered. 7 00:00:41,010 --> 00:00:49,330 So the objet in house you cannot guarantee the order they will be. 8 00:00:49,340 --> 00:00:59,940 Also while in an array you access the value base on the indexed with a hash you reference it find the 9 00:01:00,060 --> 00:01:00,810 object. 10 00:01:00,810 --> 00:01:03,470 We will have a key value. 11 00:01:04,170 --> 00:01:09,310 So the key will have a corresponding value. 12 00:01:09,540 --> 00:01:16,320 So the key difference between an array and a Hash is that Flurry is an ordered collection and it has 13 00:01:16,440 --> 00:01:19,880 is an ordered collect. 14 00:01:20,250 --> 00:01:25,860 You can reference he has via the objet in the key value pairs. 15 00:01:26,040 --> 00:01:33,850 This will make more sense when we go on to create an example hash shortly. 16 00:01:34,090 --> 00:01:36,530 Hash is identified. 17 00:01:36,730 --> 00:01:45,580 My curly braces who when you create a hash you have to have include curlee process so you create a hash. 18 00:01:45,600 --> 00:01:48,480 Basically the same way you would create a ring. 19 00:01:48,480 --> 00:01:50,240 So you start with a name. 20 00:01:50,400 --> 00:01:58,770 So I'm going to create a hash and I'm going to call it cars or car. 21 00:01:58,770 --> 00:02:06,960 Make a car single up and set it to the airport to and then need the curly braces so you need the curly 22 00:02:06,960 --> 00:02:09,870 braces in order to pull the plug. 23 00:02:09,860 --> 00:02:18,040 It's inside the house so we have to define the key and then we defined a value. 24 00:02:18,060 --> 00:02:25,300 So the key the first key unguents defined here is going to be the model of the car. 25 00:02:26,220 --> 00:02:37,540 So type in model and enclose that in quotes and then you do an equal to and greater than sign. 26 00:02:38,000 --> 00:02:42,640 When you do that now you have to give it a value. 27 00:02:42,900 --> 00:02:45,920 So we've given it the we've got the key. 28 00:02:45,990 --> 00:02:48,810 Now we need to add the value. 29 00:02:49,080 --> 00:02:51,700 So the value surrounded input. 30 00:02:52,020 --> 00:02:54,930 So my value here is going to be porsh 31 00:02:57,640 --> 00:03:05,030 P R C H E porsh so that is one value. 32 00:03:05,040 --> 00:03:08,170 That's the value of one object and do a comma. 33 00:03:08,170 --> 00:03:13,130 If you want to add more say I want to add a column. 34 00:03:13,560 --> 00:03:14,190 So you do. 35 00:03:14,190 --> 00:03:28,920 Quotes followed by the word caller and then an equal to and then a greater than sign and then the value 36 00:03:28,980 --> 00:03:30,930 of the caller. 37 00:03:31,860 --> 00:03:33,400 So I see. 38 00:03:33,930 --> 00:03:41,940 And you can go on until you know you exhausted the list but this is just an example. 39 00:03:42,210 --> 00:03:48,920 So once you done it does poorly are the curly braces to close. 40 00:03:48,930 --> 00:03:59,040 They have a few press enter it shows you that I've created a hash and this is a key for the first object 41 00:03:59,450 --> 00:04:02,130 and that is a value second object. 42 00:04:02,130 --> 00:04:05,310 This is the key that is of value. 43 00:04:05,310 --> 00:04:07,700 This is all a means by key value. 44 00:04:07,870 --> 00:04:15,530 P appears in pairs but they each value is object value object value here. 45 00:04:15,540 --> 00:04:23,240 This object key this referred to as the key and it has a corresponding value. 46 00:04:24,240 --> 00:04:31,570 What an array wait to access the octave in said array used the index with the hash. 47 00:04:31,590 --> 00:04:33,820 You can use the key. 48 00:04:34,170 --> 00:04:44,400 So if I type in the name of the hash which is car and then in square bracket I just type in in quotes 49 00:04:44,460 --> 00:04:52,890 the name of what I'm looking for so I see a model include a square bracket and actually return posh 50 00:04:53,490 --> 00:04:57,930 he can see is giving me the value of push I've typed in the key. 51 00:04:57,930 --> 00:04:59,510 It's giving me value. 52 00:04:59,780 --> 00:05:08,610 So in comparison with I raise you use the objects the key in the object to access the value outside 53 00:05:08,690 --> 00:05:12,700 access the values inside the hash. 54 00:05:12,740 --> 00:05:16,700 You can also access the key if you want it to access the key. 55 00:05:16,700 --> 00:05:22,340 For example I can typing car dot key 56 00:05:25,550 --> 00:05:31,950 and then just to type in the name of the key. 57 00:05:34,210 --> 00:05:34,690 People 58 00:05:38,410 --> 00:05:43,550 see it and press enter. 59 00:05:43,720 --> 00:05:48,730 That is giving me a model so you can also do it this way. 60 00:05:49,040 --> 00:05:55,960 All right so that's basically the kid defend it in an RV and it has to if you want something that you're 61 00:05:55,960 --> 00:06:01,720 not you don't care what order then you can use the hash if you want something that is structured to 62 00:06:01,720 --> 00:06:03,210 want a certain order. 63 00:06:03,580 --> 00:06:05,540 Then Harry is the way to go. 64 00:06:05,590 --> 00:06:08,060 So there's a lot you can do with hashes. 65 00:06:08,290 --> 00:06:14,820 It works similarly to areas where you can manipulate them just as you would agree as well. 66 00:06:14,930 --> 00:06:18,110 So that's it for this brief introduction to. 67 00:06:18,130 --> 00:06:19,120 He has. 68 00:06:19,120 --> 00:06:24,100 You can read more about it on the ruby documentation. 69 00:06:24,130 --> 00:06:25,650 Many thanks for watching. 70 00:06:25,730 --> 00:06:26,790 Bye for now.