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These are the user uploaded subtitles that are being translated: 1 00:00:00,990 --> 00:00:06,580 Hello everyone and welcome to the lecture on vector basics and this lecture were to learn how to construct 2 00:00:06,580 --> 00:00:11,880 the vector using the combined function the different rules about constructing a vector and how to use 3 00:00:11,880 --> 00:00:15,600 the names function to assign names to each element in our vector. 4 00:00:15,600 --> 00:00:18,960 Let's go ahead and jump to our studio to get started. 5 00:00:18,960 --> 00:00:25,920 All right so here our studio and let's discuss the vector so vector is just a one dimensional array 6 00:00:25,920 --> 00:00:31,620 that can hold character numeric or logical data elements and we create a vector by using the combined 7 00:00:31,620 --> 00:00:34,570 function which is just the letter c of some parentheses. 8 00:00:34,830 --> 00:00:37,930 So let's go ahead and create a couple of factors. 9 00:00:37,980 --> 00:00:40,560 We'll start by creating a vector of numerics. 10 00:00:40,590 --> 00:00:47,670 So I'll call this NBC as the variable name of the assignment operator that little arrow and then use 11 00:00:47,670 --> 00:00:54,030 the combined function which is that C lose some parentheses and then pass an individual elements separated 12 00:00:54,030 --> 00:00:55,260 by a comma. 13 00:00:55,260 --> 00:01:02,970 So let's just say one two three four five separated by commas and notice in my environment I have NVC 14 00:01:03,720 --> 00:01:10,380 and if I call NABC I get back my one dimensional array of those five elements and we can go ahead and 15 00:01:10,380 --> 00:01:18,180 call class on NVC and all return numeric since every element in that vector is a numeric. 16 00:01:18,180 --> 00:01:20,480 Let's go ahead and just see a couple more examples. 17 00:01:20,520 --> 00:01:29,250 Let's say I wanted a vector of characters let's call it C C and we'll just go ahead and pass in USA 18 00:01:29,290 --> 00:01:29,360 . 19 00:01:29,370 --> 00:01:36,500 So you will say s a. 20 00:01:36,960 --> 00:01:42,900 And remember to put in the C here for the combined function in order to actually create that vector 21 00:01:43,320 --> 00:01:47,250 c v c and then we have USA. 22 00:01:47,280 --> 00:01:47,720 All right. 23 00:01:47,720 --> 00:01:51,900 And if I check the class it's going to return character. 24 00:01:51,930 --> 00:01:55,380 Finally let's get a vector of logicals. 25 00:01:55,380 --> 00:02:04,050 So those boolean values and we'll just say T capital T capital F stands for true false LGC is true false 26 00:02:04,050 --> 00:02:04,080 . 27 00:02:04,080 --> 00:02:08,260 And if I check the class of that it's a logical. 28 00:02:08,430 --> 00:02:09,070 All right. 29 00:02:09,390 --> 00:02:14,970 So something to note here is you may be wondering well what if I try to put in different data types 30 00:02:15,270 --> 00:02:16,360 into a vector. 31 00:02:16,380 --> 00:02:18,670 What would the class function return. 32 00:02:18,690 --> 00:02:24,390 So one of the rules about vectors is that you can't mix data types into the elements of that vector 33 00:02:24,390 --> 00:02:29,060 array R will convert the other elements to force everything to be of the same class. 34 00:02:29,070 --> 00:02:31,890 We're going to show you an example of how that would work. 35 00:02:31,890 --> 00:02:41,970 So going to create a variable v and then going to try to combine let's say a logical true with some 36 00:02:42,060 --> 00:02:45,120 numbers 20 and 40. 37 00:02:45,120 --> 00:02:51,030 So if I try doing that they'll notice if I call back that vector V that true has been converted to a 38 00:02:51,030 --> 00:02:52,660 numeric one. 39 00:02:52,980 --> 00:02:56,980 And that is going to be because everything else in that vector was numeric. 40 00:02:57,030 --> 00:02:59,250 So if I call class on the. 41 00:02:59,400 --> 00:03:01,640 Everything has been converted to a numeric. 42 00:03:01,650 --> 00:03:06,720 Likewise if I put in false that false would have been converted to a 0 number. 43 00:03:06,820 --> 00:03:11,040 Let's show you another example of mixing data types. 44 00:03:11,040 --> 00:03:22,160 Let's say I had a character let's say just USA as a string and some numbers 20 31. 45 00:03:22,200 --> 00:03:26,080 You might be thinking well how can USA be converted into a numeric. 46 00:03:26,160 --> 00:03:31,300 Well in this case what are we going to do it's going to convert everything else into a character. 47 00:03:31,320 --> 00:03:34,640 So everything matches the character of USA. 48 00:03:35,040 --> 00:03:40,950 So if I call in class VI now everything in that vector is a character Scotius something to keep in mind 49 00:03:40,950 --> 00:03:40,970 . 50 00:03:40,980 --> 00:03:44,190 You can't mix up these data types elements in a vector. 51 00:03:44,190 --> 00:03:49,320 Later on we'll learn about other data structures such as a list which will allow us to mix and match 52 00:03:49,320 --> 00:03:53,360 different data types into an organizational array. 53 00:03:53,370 --> 00:03:54,140 All right. 54 00:03:54,390 --> 00:03:58,360 With that being said let's go ahead and talk about vector names. 55 00:03:59,280 --> 00:04:02,900 So let's imagine we had a vector of temperature data. 56 00:04:02,970 --> 00:04:10,200 So I go in and clear this make a new vector called temp's and put in some temperature data. 57 00:04:10,200 --> 00:04:17,850 Let's go ahead and say 72 degrees 71 degrees and some other just numbers and good and fill these in 58 00:04:17,850 --> 00:04:22,010 as you see fit 75. 59 00:04:22,010 --> 00:04:29,370 So let's go ahead and make one for each week day so Monday Tuesday Wednesday Thursday Friday Saturday 60 00:04:30,240 --> 00:04:32,320 Sunday. 61 00:04:32,370 --> 00:04:33,060 All right. 62 00:04:33,390 --> 00:04:38,760 So these are in Fahrenheit hopefully Celsius will be quite hot. 63 00:04:38,970 --> 00:04:40,300 So we are temps. 64 00:04:41,040 --> 00:04:48,540 And if you notice very cold temps back I have an array of numbers but no names to associate with each 65 00:04:48,540 --> 00:04:49,950 of those temperatures stand for. 66 00:04:49,950 --> 00:04:55,590 So I don't know if the Week starts at Sunday or Monday here and I want to add that information and I 67 00:04:55,590 --> 00:04:58,200 can do that using the names function. 68 00:04:58,620 --> 00:05:08,550 So I'm going to go ahead and say names pass in the vector that I want to name and then apply or assign 69 00:05:08,790 --> 00:05:12,470 a vector of names for the temps vector. 70 00:05:12,660 --> 00:05:17,160 So it's going to started off on Monday so I'll say Tuesday 71 00:05:20,310 --> 00:05:21,030 Thursday 72 00:05:25,220 --> 00:05:37,860 will say Friday Saturday Sunday say the sun makes sure that one last ones in single quotes or double 73 00:05:37,860 --> 00:05:39,360 quotes. 74 00:05:40,490 --> 00:05:46,430 OK so I've been able to assign names to each of these elements if I cold temps. 75 00:05:46,430 --> 00:05:49,340 Now notice the output. 76 00:05:49,410 --> 00:05:52,530 Now each of these temperatures has been assigned a name. 77 00:05:52,530 --> 00:05:56,820 This is going to be really useful because now later on we learn about indexing vectors. 78 00:05:56,850 --> 00:06:00,520 I can use these names to grab data out of the vector. 79 00:06:00,840 --> 00:06:05,600 Something to note is that I don't have to keep rewriting this long vector of weekdays. 80 00:06:05,610 --> 00:06:13,980 I could just assign this vector to let's say a vector called days may go ahead and do that in the press 81 00:06:14,130 --> 00:06:19,370 on the up arrow on my keyboard and let's go ahead instead of using names here. 82 00:06:19,410 --> 00:06:25,150 When I'm going to do is assigned this to a new vector called days. 83 00:06:25,590 --> 00:06:27,090 So never called days. 84 00:06:27,180 --> 00:06:33,450 I have this character vector of day information on Monday Tuesday etc. and then I can do this sort of 85 00:06:33,450 --> 00:06:36,810 operation names temps 86 00:06:40,620 --> 00:06:43,250 and assign days to it in this format. 87 00:06:43,470 --> 00:06:48,200 So usually when you're doing names obviously will get the same result here same vector. 88 00:06:48,360 --> 00:06:52,740 But as I mentioned usually in reading names you're not going to write this whole long vector multiple 89 00:06:52,740 --> 00:06:54,410 times feasible times. 90 00:06:54,480 --> 00:07:00,730 Your first assigned to a vector like so and then use that vector in your name assignment later on. 91 00:07:00,740 --> 00:07:06,690 OK so let's just go over everything we learned just quickly throughout this lecture. 92 00:07:06,690 --> 00:07:11,700 We learn how to use the combine function which is c and if you can go ahead and check out the history 93 00:07:12,720 --> 00:07:14,060 here on this panel. 94 00:07:14,100 --> 00:07:16,430 So we took out the combined function. 95 00:07:16,440 --> 00:07:22,410 Learn how to use it learn that vectors can only take up one data type otherwise other data types will 96 00:07:22,410 --> 00:07:23,390 be converted. 97 00:07:23,430 --> 00:07:27,010 We learn how to use names and learn about the vector assignment. 98 00:07:27,350 --> 00:07:32,740 OK later on we're going to learn much more about how to use and work with vectors in our. 99 00:07:32,790 --> 00:07:35,040 Thanks everyone and I'll see you at the next lecture. 10280