1 00:00:00,830 --> 00:00:06,410 Hey guys this video we're going to start to work with numbers and also the math object. 2 00:00:06,420 --> 00:00:12,600 So what we're going to do here is we're going to set two numbers so I'll say Konst number one and let's 3 00:00:12,600 --> 00:00:15,060 get this to 100. 4 00:00:15,060 --> 00:00:20,810 Let's get to to 50 and I'm going to set. 5 00:00:20,830 --> 00:00:23,170 Going to initialize a vowel variable. 6 00:00:23,250 --> 00:00:27,650 OK because we're going to be basically mutating this variable as we go along. 7 00:00:27,840 --> 00:00:35,600 All right and then down at the bottom here I just want to console log the val. 8 00:00:35,760 --> 00:00:36,380 All right. 9 00:00:36,870 --> 00:00:39,600 So first thing I want to look at is just basic math. 10 00:00:39,740 --> 00:00:40,070 OK. 11 00:00:40,080 --> 00:00:54,410 So simple math with numbers so we can say we'll take that well and we'll set it to number one plus two 12 00:00:54,420 --> 00:00:55,580 and this is very easy. 13 00:00:55,580 --> 00:01:02,090 Very simple stuff guys I know that but I do you know this is for beginners to advance so we need to 14 00:01:02,090 --> 00:01:03,280 cover everything. 15 00:01:03,380 --> 00:01:07,360 So we'll save that and obviously down here we're going to get 150. 16 00:01:07,370 --> 00:01:15,420 All right so in addition to addition of course we can do it say multiplication save that we get five 17 00:01:15,420 --> 00:01:16,650 thousand. 18 00:01:17,330 --> 00:01:20,810 Let's do subtraction. 19 00:01:21,590 --> 00:01:25,200 We get 50 let's do division. 20 00:01:26,060 --> 00:01:26,970 We get two. 21 00:01:26,990 --> 00:01:32,540 And let's do the modulus operator which will basically give us what's left over as a remainder. 22 00:01:32,540 --> 00:01:34,830 So if we save that we get zero. 23 00:01:35,060 --> 00:01:35,390 All right. 24 00:01:35,390 --> 00:01:41,180 If I were to change this to let's say 60 and say we're going to get 40. 25 00:01:41,210 --> 00:01:41,590 All right. 26 00:01:41,630 --> 00:01:45,720 Now I using me I don't actually use this modulus that much. 27 00:01:45,950 --> 00:01:49,280 But those are the basic math operators. 28 00:01:49,280 --> 00:01:57,650 Now there's a math object we can use to do certain things like round get the absolute get get the power 29 00:01:57,650 --> 00:02:04,980 of something generate random numbers things like that so we're going to take a look at that. 30 00:02:05,030 --> 00:02:09,500 All right so let's take that vow and let's set that. 31 00:02:09,740 --> 00:02:11,860 First of all I want to do math Daut pi. 32 00:02:11,860 --> 00:02:16,270 So math is an object meaning that it has properties and methods. 33 00:02:16,280 --> 00:02:17,060 OK. 34 00:02:17,090 --> 00:02:22,960 A property is basically like an attribute and then a method is just a function. 35 00:02:23,000 --> 00:02:26,450 Ok it's a function inside of a private inside of an object. 36 00:02:26,480 --> 00:02:31,730 So pi as you can probably yes is just going to give us pi if I say that we're going to get that three 37 00:02:31,730 --> 00:02:34,310 point 1 4 1 whatever. 38 00:02:34,310 --> 00:02:40,010 We also have and there's there's a few other ones that I'm not going to mention that I've never even 39 00:02:40,010 --> 00:02:44,840 thought about using this as ular as numbers so math thought me save that. 40 00:02:44,840 --> 00:02:50,000 That gives us this number here and then we're going to look at some helpful methods. 41 00:02:50,000 --> 00:02:50,330 All right. 42 00:02:50,330 --> 00:02:55,320 So if you want a round number let's say value equals math. 43 00:02:55,400 --> 00:02:56,090 Round 44 00:02:58,850 --> 00:03:03,540 so round and let's do to say two point eight. 45 00:03:03,560 --> 00:03:05,730 So that's going around 2 3. 46 00:03:05,900 --> 00:03:10,230 If we do two point four that's going around to two. 47 00:03:10,430 --> 00:03:15,170 Now there's going to be times when you want to specify if you want to round up or down. 48 00:03:15,170 --> 00:03:18,280 So for that we have Seal and floor. 49 00:03:19,250 --> 00:03:24,130 So for instance if we want to round up we'll do seal. 50 00:03:24,770 --> 00:03:30,080 And even if we put two point four in here and save we're going to get three. 51 00:03:30,120 --> 00:03:30,620 All right. 52 00:03:30,620 --> 00:03:37,910 And then at the same time we have math thought floor where if we put two point eight and save we're 53 00:03:37,910 --> 00:03:39,270 going to get two. 54 00:03:39,830 --> 00:03:40,800 OK. 55 00:03:41,300 --> 00:03:50,780 Now if we want to square something we can say the math Daut square root or s q r t. 56 00:03:50,780 --> 00:03:55,300 So let's say we want to square 64 save we get a. 57 00:03:55,780 --> 00:03:59,000 All right if we want to get the absolute number. 58 00:04:00,290 --> 00:04:07,340 So say math thought abs that will give us the absolute numbers so if we put a negative number in here 59 00:04:07,340 --> 00:04:12,000 it's going to give us the positive version of it which is the absolute version of it. 60 00:04:12,050 --> 00:04:19,940 All right if we want to get the power of something we can say vowel equals math dog POW. 61 00:04:20,650 --> 00:04:30,530 All right so let's say we want 8 to the second and save and we get 64 OK. 62 00:04:30,560 --> 00:04:33,020 We also have min and max. 63 00:04:33,020 --> 00:04:38,000 So let's say value equals math thought men. 64 00:04:38,180 --> 00:04:44,270 And then this actually takes in some comma separated values so let's just put some random numbers in 65 00:04:44,270 --> 00:04:45,510 here. 66 00:04:49,230 --> 00:04:55,470 And we'll save and I'm just going to return whatever the minimum is and that's one and we can also put 67 00:04:55,470 --> 00:05:00,160 negative numbers in here so obviously if I put negative two that's going to be the men. 68 00:05:00,640 --> 00:05:04,890 OK and as you can probably guess we also have a max method. 69 00:05:04,890 --> 00:05:12,620 So if I change this to Max and save we get 55 which is the max number. 70 00:05:12,630 --> 00:05:12,980 All right. 71 00:05:12,980 --> 00:05:17,100 So we also have a helpful method called random. 72 00:05:18,040 --> 00:05:20,490 So math Daut random. 73 00:05:20,490 --> 00:05:24,830 Now what this does is it gives us a random decimal. 74 00:05:24,840 --> 00:05:28,200 So if I keep reload here you'll see it'll keep changing. 75 00:05:28,200 --> 00:05:32,130 Now in a lot of cases you're going to want a random whole number. 76 00:05:32,160 --> 00:05:32,520 So. 77 00:05:32,580 --> 00:05:36,970 So just using math dot random isn't going to help you. 78 00:05:37,050 --> 00:05:44,910 So a solution to this would be to say that all equals and we'll use the math thought random which will 79 00:05:44,910 --> 00:05:49,860 generate a random decimal and then multiply it by the max number we want. 80 00:05:49,860 --> 00:05:51,200 So let's say 20. 81 00:05:51,360 --> 00:05:57,750 So if I go ahead and save this and we look down here this is going to give us a random number with a 82 00:05:57,750 --> 00:06:02,570 decimal are between 0 and 19. 83 00:06:02,580 --> 00:06:02,930 All right. 84 00:06:02,940 --> 00:06:10,150 Now you're probably going to want from 1 to 20 so all you would do is just add on a 1 to that. 85 00:06:10,380 --> 00:06:15,270 OK so now it will be 1 through 20 but you probably don't want the decimals. 86 00:06:15,270 --> 00:06:20,320 So what you would do is wrap it in math for her. 87 00:06:20,370 --> 00:06:24,630 All right so we're going to round it down so we'll go ahead and wrap that up. 88 00:06:24,630 --> 00:06:26,070 The whole thing save. 89 00:06:26,160 --> 00:06:32,440 And now we're going to get a random number between 1 and 20 Always. 90 00:06:32,460 --> 00:06:32,970 All right so. 91 00:06:33,000 --> 00:06:37,440 So this is something that you see it's very very common in javascript. 92 00:06:37,440 --> 00:06:40,790 All right guys so in the next video we're going to work with strings. 93 00:06:40,800 --> 00:06:42,630 So we're going to look at concatenation. 94 00:06:42,630 --> 00:06:48,540 We're going to look at some of the different methods to change a string to upper case or to replace 95 00:06:48,540 --> 00:06:52,070 something in a string to pluck something out of a string. 96 00:06:52,370 --> 00:06:57,790 How to turn a string into an array things like that things that are used all the time in projects. 97 00:06:57,780 --> 00:06:58,380 All right. 98 00:06:58,470 --> 00:07:04,500 So I know that this stuff isn't as exciting as building something as building a project but it's all 99 00:07:04,500 --> 00:07:09,750 fundamental knowledge that you need in order to be able to do that and actually understand what's going 100 00:07:09,750 --> 00:07:15,750 on and not just do a code along you know so we will get into projects but we need to cover these fundamentals 101 00:07:15,750 --> 00:07:16,290 first. 102 00:07:16,290 --> 00:07:17,130 So that's it. 103 00:07:17,130 --> 00:07:18,560 I will see you in the next video.