1 00:00:00,390 --> 00:00:03,969 All right, so the next challenge gets a little bit harder. 2 00:00:04,110 --> 00:00:10,200 It's like we're doing our sit ups now. In this challenge, you're going to be drawing a triangle, square, 3 00:00:10,200 --> 00:00:13,950 pentagon, hexagon, heptagon, octagon, nonagon, and decagon. 4 00:00:14,220 --> 00:00:21,180 So from three-sided shape to ten-sided shape and each of those shapes is going to be drawn with a random 5 00:00:21,180 --> 00:00:26,340 color, and each of the sides are going to be 100 in terms of length, 6 00:00:26,700 --> 00:00:34,470 and the final outcome should look something like this. All of these shapes overlaid on each other and 7 00:00:34,470 --> 00:00:36,390 drawn out in sequence. 8 00:00:37,140 --> 00:00:42,900 So you'll have to think a little bit about this because we know that a square has 90-degree angles. 9 00:00:43,230 --> 00:00:48,980 So we could get our robot to go forwards and then turn right 90 degrees and then go forwards again. 10 00:00:49,470 --> 00:00:51,430 But what about a Pentagon? 11 00:00:51,690 --> 00:00:52,890 Well, a pentagon, 12 00:00:52,890 --> 00:00:56,210 each of the corners has a 72 degree angle. 13 00:00:57,390 --> 00:00:59,330 So what's the actual relationship? 14 00:00:59,340 --> 00:01:00,570 How can we work this out? 15 00:01:01,110 --> 00:01:05,700 Well, we know that to turn a full circle, it's 360 degrees. 16 00:01:06,150 --> 00:01:14,370 So the way you work out the angle of each of these shapes is by dividing 360 by the number of sides. 17 00:01:14,730 --> 00:01:17,410 So 360 divided by five is 72. 18 00:01:17,490 --> 00:01:20,700 So each of the corners is 72 degrees. 19 00:01:21,570 --> 00:01:27,000 Using this knowledge and what you've learned about Turtle, go ahead and see if you can complete this 20 00:01:27,000 --> 00:01:27,570 challenge. 21 00:01:27,750 --> 00:01:29,400 Pause video now and give it a go. 22 00:01:32,880 --> 00:01:36,840 All right, so I'm going to delete the previous code and we're going to write the code that's going 23 00:01:36,840 --> 00:01:43,560 to draw all of these shapes. The first thing I want to do is I want to put down that equation. So we 24 00:01:43,560 --> 00:01:51,550 know that if we have 360 degrees divided by the number of sides, then we get the angle, right? 25 00:01:51,780 --> 00:01:55,620 So let's save that into a variable called angle. 26 00:01:56,520 --> 00:02:02,840 And then all we have to do is to get our robot to go forwards 27 00:02:04,350 --> 00:02:13,800 by 100, we said. And then to get it to turn right and the angle that it's going to turn right by is 28 00:02:13,800 --> 00:02:16,320 the one that we defined at the top there. 29 00:02:17,010 --> 00:02:22,680 So then we just need this to be repeated for as many times as we have number of sides. 30 00:02:23,580 --> 00:02:25,830 So we could create a for loop, for example. 31 00:02:27,520 --> 00:02:31,120 And the range is going to take into account the number of sites. 32 00:02:32,650 --> 00:02:39,520 So now if the number of sites is equal to let's say five, let's say we're trying to draw a pentagon, 33 00:02:40,090 --> 00:02:42,050 then this would be the code. 34 00:02:42,640 --> 00:02:44,170 So let's shift that along. 35 00:02:44,530 --> 00:02:47,200 And now if we go ahead and run this code, 36 00:02:48,680 --> 00:02:56,900 you can see it draws us a pentagon, a five-sided shape. So how can we get this loop to run for the 37 00:02:56,900 --> 00:02:58,220 different sides? 38 00:02:58,700 --> 00:03:07,550 How can we get it to go from a three-sided shape, a triangle, all the way to a ten-sided shape, a decagon? 39 00:03:08,780 --> 00:03:13,220 To do this, instead of setting the number of sides statically like this, 40 00:03:13,530 --> 00:03:16,700 why don't we create a function? Let's call it draw_shape. 41 00:03:17,270 --> 00:03:24,470 And this function is going to take the number of sides that this shape has as an input. 42 00:03:24,980 --> 00:03:29,660 And then the rest of this code can be indented inside the function. 43 00:03:30,260 --> 00:03:33,890 And it probably makes sense to only calculate the angle once 44 00:03:34,130 --> 00:03:39,080 when we need to draw the shape because for the given number of sides, that angle is going to be the 45 00:03:39,080 --> 00:03:41,340 same across the entire shape. 46 00:03:42,500 --> 00:03:48,950 For example, if it was a square then we're going to go from one to four drawing this four times. 47 00:03:49,700 --> 00:03:56,960 So now later on, we can define another for loop and this for loop is going to go through all of the 48 00:03:56,960 --> 00:03:59,270 different number of sides that we need. 49 00:03:59,870 --> 00:04:06,560 Now, if we want a range of numbers between 3 and 10, we actually need to write the function 3, 50 00:04:06,560 --> 00:04:10,700 11, because the stop number is excluded 51 00:04:10,710 --> 00:04:14,150 so it'll stop at 10. As we loop through this range. 52 00:04:14,570 --> 00:04:21,010 this shape_side_n is going to take on the value depending on where we are in the range. 53 00:04:21,350 --> 00:04:26,630 So when we're first drawing this, we're going to draw a triangle with three sides so then we can pass 54 00:04:26,630 --> 00:04:33,380 this shape_side_n into our draw_shape function and that should go from 3 to 10. 55 00:04:33,920 --> 00:04:40,970 So let's run our code and see it draw our triangle first and then our square and then it just keeps 56 00:04:40,970 --> 00:04:44,000 on going until it draws all of the shapes that we need. 57 00:04:45,020 --> 00:04:51,030 Now, the very last part of the challenge is to make each of the lines a different random color. 58 00:04:51,560 --> 00:04:53,090 So how can we do this? 59 00:04:54,440 --> 00:04:59,270 So, of course, we're going to go to our good friend Google and we're going to search for the turtle 60 00:04:59,270 --> 00:05:01,140 colors in Python. 61 00:05:01,370 --> 00:05:08,510 I first tried to Google this without the python, and I got the different colors of various turtles, 62 00:05:08,840 --> 00:05:10,280 which was really fascinating 63 00:05:10,280 --> 00:05:11,980 but that's not what I wanted. 64 00:05:12,560 --> 00:05:14,270 So if we take a look at the first link 65 00:05:14,630 --> 00:05:21,260 this comes from a website called Trinket, and it has this interactive color palette where you can select 66 00:05:21,260 --> 00:05:27,740 one of these colors that you like and then you'll get the turtle name, which then you can copy and 67 00:05:27,740 --> 00:05:30,230 paste into maybe a list. 68 00:05:30,740 --> 00:05:31,910 Let's call it colors. 69 00:05:34,180 --> 00:05:39,940 And you can put as many colors into this palette as you want, and you can make it as extensive or as 70 00:05:39,940 --> 00:05:41,200 short as you want it to be. 71 00:05:41,860 --> 00:05:44,490 So here's a list that I created earlier. 72 00:05:44,950 --> 00:05:55,990 And now, if we go ahead and set our turtle's color, so let's go ahead and get Tim and set his color to 73 00:05:56,020 --> 00:06:03,160 a random color from this list which we know to be as simple as simply importing the random module 74 00:06:03,550 --> 00:06:06,880 and then we can get hold of the random. choice 75 00:06:07,240 --> 00:06:14,080 and then inside that method, we can pass in our list of colors so that it picks a random color from 76 00:06:14,080 --> 00:06:14,680 that list. 77 00:06:15,280 --> 00:06:16,990 So now let's run it again, 78 00:06:16,990 --> 00:06:23,860 and you can see each time the shape is being drawn it's picking a random color from our list of colors. 79 00:06:24,610 --> 00:06:25,680 So there you have it. 80 00:06:26,020 --> 00:06:28,680 That's the solution to this challenge. 81 00:06:29,140 --> 00:06:34,330 And this was a little bit more challenging I would say because we're doing functions and loops and 82 00:06:34,330 --> 00:06:37,780 you have to get hold of some colors and you have to figure all of that out. 83 00:06:38,050 --> 00:06:42,700 But hopefully you've managed just fine and you're ready to move on to the next challenge.