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00:00 mm hmm. There's been a lot examples on everything. Every new concept

00:20 Yeah. So what are the types watching out there actually go to

00:27 Sure. Okay. So um presentable before the break, I started to

00:36 about ordinary differential equations. So that's I want to continue to talk

00:44 right? Yeah, it does. this is kind of a international last

00:54 too best. And so it's that's problem formulations where the problem is kind

01:01 defined by change or differential. So one knows the rate of change of

01:09 and then Bill starts the thing that thought you might be familiar with.

01:15 other thing is also Newton's second bomb this process. Change in velocity is

01:21 function of acceleration. So sometimes problems formulated in this differential form and for

01:30 of the action Simple Thing, there just one the question. But this

01:37 where ah things are over time for , they can always than the other

01:45 being in space and solution or a in some sense that one was to

01:55 terrible. Sometimes they use explicit notation sometimes just use it. You

02:02 everything big. And then I'll also this one the simple one where we

02:10 to solve this one can retest that kind of a problem with integration,

02:14 for nothing before. So it's just with buying up the or on the

02:19 hand side and through the integration. then of course that gets um it

02:25 often the but I never want that's function on the body that have at

02:31 see where we start and then there to think the grill um the right

02:38 side and so the most money break basically I believe that this value is

02:47 in the intervals of tangents and I to the end and that is what's

02:54 as the oilers method that there's some here. Um I'm gonna assume again

02:59 this is a constant On the previous . The other one that also went

03:07 Greece last time is then instead of this simple assumption, look at the

03:14 and using it. Doctors order. put it on the disorder role.

03:20 use the function values of the two and then there will be a range

03:28 . So that is this formula Oh my camera is off.

03:35 wow. Yeah. Okay. Sorry about that. So mm

03:46 But as we pointed out the problem this one we want fine Next the

03:53 . But we also have that one right hand side. So whereas in

03:58 one there is no beyond anything to where we are at time. T

04:03 this case both the left and the hand side has the same animal

04:07 So that this what it means to what? Not anymore. No.

04:17 . Um look in the middle I so it ends up being somewhere

04:25 No. So this was what's known an implicit formula where is this guy

04:30 here is explicit because it doesn't including future values. That is not

04:37 So we'll come back and most of things that we're talking about today are

04:42 methods or all the methods for its . Alright. So that's what wants

04:50 know something that they did not talked last time. Is this kind of

04:56 picture? So sometimes it is So this is simply look at some

05:06 of X values and some range of news and whatever you choose to plug

05:14 here. You can evaluate the function which is basically and tell them what

05:20 slope of a curve going through that would be. Now these vector fields

05:27 be used for a number of the I've talked about today but it's also

05:32 used in computer graphics where they generate these values and there's good trace depending

05:40 where you start show these different cards this spot is for different values of

05:46 . That the story. So depending you start whatever the solution follow some

05:53 and process. So then for So here is one of the

06:01 Have you can follow us generated values different points and sometimes you can inject

06:07 particles. A lot of the fluid people like to do. Yes,

06:15 particles and then follow the force Figure out something. Or I think

06:21 for these things from someone if you this part. Mm hmm I followed

06:29 brief mm mm mm mm mm mm mm mm. Well for us it

06:36 work. So you can follow basically of electricity language and that smoke and

06:41 how things evolve something that is being . There's another one I guess difficult

06:48 this one too. Yes sir. to give you some notion of what

06:54 very difficult sometimes. Mm hmm. and here's another one. Again,

07:03 back to this kind of a few . And the point of this one

07:07 just to show that someone gave some equations for all these um, are

07:15 of tricky in the sense that from Fargo these are basically a whole

07:21 of trajectory is the difference in the and the stolen values and this kind

07:30 vibrant shades in very different directions. for very small changes from the initial

07:36 don't need to be conscious is a bit about the properties of these

07:40 how they're going to behave. Not . But thank you. Stop.

07:49 another thing discovered in France is kind uniqueness of solution. The science of

07:59 process of things over our behavior In areas around value horses and supporting your

08:04 zero and 0. And it's some domain around both have really city range

08:13 time and in the solution. The if things are going overhead in terms

08:18 the function and its derivative, then can also say that solution is,

08:26 we're using their So it's unique. as long as these conditions, the

08:36 , wow. So now I talked some real methods for solving the differential

08:46 and What kind of unit three basic . It's always so serious is an

08:57 . Not necessarily good option, but is an option. Other ones are

09:02 I would say using the intuition about white fields because you want to construct

09:11 . But basically looking at the vector and you're sampling in the vector

09:17 And the third is things going back from the early space today is how

09:24 do integration Over the small interval from plus H. And looking at an

09:33 formulation of in their own ladies. now there is a serious methods.

09:42 There was serious expansion, you straightforward as 15 many times by

09:47 And depending on how many terrorists an in gold, you've got the method

09:55 some order and the order is determined the highest derivative. That could be

10:00 in the expansion. And then there some truncation follows. So I'll give

10:07 a couple of examples of using the series expansion. And then if the

10:15 is not used. But it's useful as always trying to understand how accurate

10:22 only have two lives. They're going go back use and trying to figure

10:28 the other methods farthest back up in of the taylor series expansion. So

10:37 hmm. Okay. The first thing I am equals man, just include

10:41 first derivative. So basically these three , which is what we did

10:47 Which is this obvious method. So what having a function that ex prime

10:53 given. That's the function itself. that's the first two terms is X

10:58 H of X crime. But X is given a F. So this

11:02 just following the slope of the green . That's what the prediction prediction would

11:08 then or what the function value X a small incremental same time from

11:20 So that's the only matter. And the facilities, gold and everything.

11:24 not I don't think anything to comment just there. And here's a little

11:29 of an example um uh the shortest of the Higgs. And as you

11:37 see, so you know that either access the function was delivered in

11:42 the function itself. So we know this is exponential functions. Um I

11:50 on this block here we have the is the actual be today. See

11:59 the other one is step by step the owner smith So why are the

12:08 always, you know, why So one thing we can see here

12:29 almost at the gap in the blue . The true solution and the productive

12:38 girls in the gap becomes quite real the volunteers as for why this

12:48 Yes. Is it bad? Ah one of the initial points it was

12:55 little bit under where the actual value . And because of the nature of

13:00 exponential equation, if it's a little lower than what the ultraviolet they're

13:05 That's correct. The tangent at any point, right? All of the

13:11 , the current trends up. But tangent is a straight line.

13:14 So if you progress from one point the next along the tangent, it

13:18 always come to be under the actual . And that then accumulates that you

13:23 going and then for the next one already start below and it gets

13:29 So but one other inheritance. Not great property or all the methods that

13:39 trying to tend to accumulate as you , overall. Mm hmm. China's

13:44 taxes practice the independent variable team of . Mm hmm. Yeah. So

13:55 in order so that was kind of . So that we talked about

13:59 So them just including the say first couple of terms usually doesn't give good

14:06 in savannah. The option is to better accuracy to use more terms than

14:13 mhm. And the thing that that that truncation error is much following

14:20 So yes, I'm doing it five example. Yes. But in this

14:28 it's almost like that feeling differential There's someone here. Yeah. What

14:35 use more terms in the taylor series in heaven. In this case we

14:41 through Potatoes years method have ordered four including 4th definitive as well. So

14:49 just starting out and taking the derivative X prime users, the second derivative

14:55 then from changing roulette sector so we all these expressions for the higher order

15:03 and then we plug it in and it is the taylor series expansion and

15:08 from there in this expression In this and then stopped here in the 4th

15:15 techniques areas and but I mean stepped of the things we need to have

15:24 expressions and if you're lucky like cheater it's an analytic expressions that we can

15:31 and the olympic television and this is enough to use my hands but if

15:38 a complicated function or we don't have nice and addictive expression. One that

15:45 to do it from America differentiation Before it's not kind of sensitive like

15:51 do something they want to avoid because that they have put on errors and

15:58 self but he was kind of the result here. It was just police

16:03 to charms and this is amusing. the approximation of the previous line.

16:09 then we get the value that is and and that's what they just to

16:18 that its approximation errors in the formula not the american position. That makes

16:24 difference is that higher order position They use cauliflower position. People are very

16:32 evaluation of this year's national workforce. fact that these two were called just

16:38 just trying to show that it The difference between these two are not

16:44 around though. In terms of the position it is the approximation area,

16:50 difference between Mr So it was just it's critical that we use for this

17:00 that. So they kind of wrote has this kind of order or nested

17:07 being and I think that's a minor . So the one thing, It's

17:12 of worth $20. What is the thing is this one? So what

17:19 did here to find all the instances of doing an instrument of both.

17:28 is O. T plus H which an infinite position is the same.

17:33 every time you get the round off then the round off and that's why

17:39 computing the new T is larger than using democracy complications. That gives you

17:49 the accumulation of error and figuring out the next issue. But that's one

17:56 . Think about the one that told more events accumulation. There are some

18:02 kind of activity from this star. right. Mm hmm. Yeah.

18:15 one thing that I guess I've been before about the taylor series expansion.

18:23 the local transportation error in a sense it's completed T plus H. It's

18:30 from the starting point. So basically local truncation error means you have an

18:36 . Um, in each step of algorithm will complete the two plus H

18:41 plus two. This one in every , in that case you have a

18:46 plantation error And then the greatest example was 4th order. So that means

18:52 local translation is only and then potentially you don't care the older and the

19:00 . The fact that there's no Alright. And then suggests. And

19:09 those are the approximation error in terms the expansion and as I mentioned the

19:17 then the results? Yeah. Right. Right. So here's the

19:33 line is well that means you need evaluate the function itself and the need

19:39 evaluate derivatives and if you have an depression, that's okay. But if

19:44 don't then numerical differentiation and that tends amplify. So that's why taylor series

19:56 . I'm not leaving used in solving function. So instead on the lights

20:05 methods that only the values for function and not effective. So that's what's

20:15 up next. Um And to me understand these methods, it's helpful to

20:23 of it in terms of this we on board I guess I've got a

20:30 . Mexico side. So um but so now yes, my friends are

20:44 on based on sampling this place and trying to figure out how and

20:54 Yes, these are known as methods mr came up with the initial idea

21:02 how to construct accurate higher order Just based on the value additional the

21:13 or the right hand side of the the question. So it's so I

21:21 to talk about how to do that it's a little bit or something.

21:26 wonder that it is an honor that's on the then we have the intuition

21:33 please for me. So let's show . Let's get down to the

21:43 Um So this is you then use function evaluations and depending how many you

21:52 for, how you use them the um explicit methods. Again unknown future

22:01 but I can give you very good . And the most popular put the

22:08 is what's the most 44 that means this covers up to the 4th order

22:17 in the expansion has a local transportation . Good morning. five Lights example

22:27 report. It's very simple. So one does is kind of a little

22:35 similar idea. House one being the integration in that case. Use the

22:41 of function values and then they try figure out the weight of the function

22:46 in order to get a polynomial corrected a certain order will pull him

22:53 And then there was a construction waited wait for function value, so

23:00 speak. So to me it's a bit of an idea was about to

23:06 and how we spent about constructed. and then they see a little bit

23:11 within language but it's kind of both favorite series function for digital things that

23:19 used for the fitness, serious methods then um we have function values in

23:27 uh back to space at zero. basically their functionalities and best families will

23:35 you the main here where they go little bit but it's saying the extract

23:41 direction and maybe it's a symbol in K direction and that means what that

23:49 . The right hand side here becomes function of two variables. And in

23:53 to figure out how to interpret whatever combination of function values used in terms

24:03 the taylor series function director from this . Um One needs to look at

24:10 take the serious expansion of the function and this. Well the domain between

24:19 and T plus H in terms of , whatever they arranged, they won't

24:27 things. But I'm just warning little things somewhat. I believe the expression

24:35 functionality. So so the first thing done too. Look at,

24:45 this series of attention. Um and the notation has been switched around a

24:52 times and then decide. So I . And and expertise that would

24:59 And this thing is general two variables and Y. And this is You

25:06 to identify one what's what the best them on your heart. And now

25:13 function of two variables. When you to material uh say the serious expansion

25:18 you have to treat it with respect both of the arguments for the function

25:24 irrespective something your age and something else . And then the increments of the

25:31 look unnatural voters to arguments of the And formally one tends to write it

25:37 way. Um, this is from unraveling a little bit conventions. So

25:44 , because of two arguments and its derivatives because the beach is not the

25:50 office backwards. Mhm. So I know if this is from a general

25:59 . Another courses you have a deep for accident with respect to y and

26:05 take a serious expansion. Then there a distance from moves and each one

26:09 the variables on this from moving in X direction and saying. And that's

26:18 of just a normal our thing. we had to take a serious expansion

26:25 factorial and the denominator. So when exponents of the Parenthesis zero than the

26:39 1. So that the first term especially just the function itself like mm

26:49 . For the single, A normal variable. Then the next one.

26:55 that one. And then that's kind probably pretty much direct correspondence to the

27:01 variable that age times deliberative respect for thanks to gravity with respect to Y

27:09 what other functions and the next term is um, it's just a

27:19 you know, um, evaluation invested branch of the science itself and then

27:27 for higher orders. Okay, But in this case you got one

27:33 sustained squared times The 2nd Derivative Even the experts Operating on the 2nd

27:42 and then the same thing pointer And then that first product in the

27:49 way for me, dysphoria or all parenthesis. So when I'm on the

27:57 guy and someone was going to use these things. All these previous

28:04 just taking the biggest serious expansion now we have the terms would worry about

28:09 then there is the local transportation or this case is the term we do

28:15 think road in the expansion and then to make it look like flat.

28:21 hmm. Ah function and value is a song range between X and X

28:29 H and Y. And one. . Like it wasn't before and the

28:33 taste, it was between the extreme they've already won on the subject to

28:40 . Now it's kind of the square it's not to mention not directly allow

28:49 to. That thing's a little bit combat and write them down and transportation

28:58 don't know if the derivative or has respect the facts from the substrate.

29:02 something counselor. But the derivation both the ones and they're straightforward and footage

29:21 dr right down instead of using some sign the best affected first derivative

29:31 the first time was with respect excellent can respect why and then.

29:39 The second or the third term roller taylor series expansion. Now that was

29:45 has been huh? Okay. That's here just replacing these things with the

30:00 this one and then we can continue you want to go and cancel

30:07 But then as soon as its especially these two Only going one

30:20 This takes 10 0. So those drops out and this is zero.

30:24 those stopped, stopped up. Nothing Alright. So now we get to

30:33 question on the best notation. And I was trying to do the method

30:42 method the only two. And this we're here to show the machinery used

30:51 order to use construct an explicit method arbitrary order. But once you get

31:02 the second order becomes cumbersome. So is not really used much. This

31:10 what's while you use and also desire but in order to show that construction

31:18 to work. So again, this of the vector field in this case

31:29 the laws will get the distance in respective independent variable fee. And that

31:36 some range for the dependent variable. . So in this case for this

31:47 I'm gonna clip from that for the to we're going to use the function

31:52 uh where we are basically down here the corner um D and access the

31:59 points and you know, t the that's straightforward. And and then we're

32:07 going to use some other function value the domain between T and T plus

32:13 and X X plus in this I am thanks. So whatever they

32:24 things we don't know is where we to sample the function value. So

32:30 have an alpha here that's somewhere The and three plus H perfect and ex

32:39 and the X value is being picked this particular way. So now the

32:44 is to figure out what is alpha what should all find Barras, B

32:50 what should the weights fear be of primitive values and restoring point and wherever

33:01 sampling is. So we have four . We need to figure out the

33:08 of these two and where is this of And then so then just using

33:17 two expression and problem 18 this for , that's something that looks like that's

33:25 to show up on the next time um Alright, so here is the

33:33 and the bottom as assembly showed up the points on Tuesdays, thousands and

33:38 and then we have standard taylor series and I said well they don't really

33:45 to use this one but we're going use have to select the Ws and

33:51 outputs and bearers in order to match number of terms and this famous series

33:59 , the accuracy um in the morning then we're going to the other cover

34:11 . So so um and it is that is for the crystal method of

34:20 . Yeah. They have already shown the preliminary stuff for hard evidence.

34:30 the function since we need to have expression here. Right? So we

34:34 the function respected to arguments. And they need to take a serious

34:39 Function with respect to both the first the second argument in order to be

34:43 then to compare it with the Yeah you can have some of those

34:52 here and there correspondence from what they what they want and how they interpret

34:59 this. That was former doctor this was coming from and now using what

35:06 have so without um we have the with respect to the first argument.

35:12 that's this one for each time first . And then you have the

35:21 Thanks the derivative with respect to the argument. But when we get to

35:26 renovation, both respect property, Thanks. This is the question

35:37 We have a transportation. So now conduct trying to compare the blood rather

35:48 this expression in. That corresponds to part here appearance. So we have

35:55 . h. 72 H. Kindness expression here and they can plug it

36:02 in and clean things up. We Wh and then we have another

36:09 Coming from this expression here. So was W a few times there.

36:13 that's the kind of system here. this from the W two times engines

36:21 then we'll get the rest of the . This gives us now ah using

36:30 idea of everyone and put the method sampling things in this box from the

36:36 you want in a form which basically have the function values of T and

36:46 . Which is the same thing else the Fearlessness expansion. So now we

36:51 compare what is from the method dollars . You can compare directly when the

36:59 is expansion. So here is again from the previous line and here is

37:07 famous series expansion which you're using the we now have and then the ex

37:15 minister that follows here. Next double is everything Inspector the little things and

37:23 we have the second um which is expression and pointing it in. So

37:34 with the system Using it for the Series six function using the same location

37:42 the country. So now we want and 8 to match as far as

37:49 can. And that is going to us figure enough. Right? So

37:55 have here looking identification of terms in H times F. In the taylor

38:00 expansion. So the one journal could it. W one plus W two

38:05 to be one. So we know this is a constraint on how we

38:10 these two guys and then we have here for them in front of a

38:17 comes in property that means our car two needs to be passed on similar

38:25 the next turn. But this gives , so when you're choosing um these

38:32 here such that did you have to it? And that's an equivalent to

38:38 us in this method 42. If notice here, there's three questions therefore

38:46 . So they have one thing going freedom that we use um once we

38:51 about that. So one word is to choose um cool, it's W

39:02 they are equal and a half and it follows the and so on.

39:09 in this perhaps a in order to again looking at a serious expansion of

39:20 involved in the Iran contra formula and trying to match it to the taylor

39:25 functional XD plus eight. And that us the second order, I don't

39:34 . So that's the procedure. And you can choose to use um more

39:40 or more points in the where are rectangles Oregon between and plus um some

39:52 depending on how what So in that . So I'm gonna start with

40:01 the senior to drive to see that just did the function rather in the

40:08 was K one. And for the one we got this point there was

40:12 older method and therefore then looks at alphas and betas and the Ws turned

40:21 then one yards. The points where function value, mm hmm. Is

40:28 in the domain continues the extra and that's the slope of the curve.

40:36 that corresponds to a different starting point exploring that's coming and things. So

40:41 is there value or came move At point. And then if I had

40:48 choose in K2, one would end here. Mr And at this point

40:56 this Indonesia point, the result probably and then they're gonna cut down method

41:02 order to that is just average Those predictions. And at this point here

41:10 our prediction in this case for But then obviously loved it so much

41:16 prediction. The Either or yourself or other one. It shows in this

41:22 for example, in this space This is your skills and one they're not

41:29 , I'm just trying to help So this is just pointing out that

41:36 his arbitrary choice of people, 71 72, the half that want to

41:44 all of it from this basic sounds . 2/3 since then this time with

41:48 fear stop all. That's important. just shows the 3rd degrees of freedom

41:58 use. But there still was. , you talk about the thing that

42:05 is the dominating version I would I'm going with the methods more informal

42:16 there but they also he's on the . So any questions on that.

42:31 ? Okay, so book and I it's just quite cumbersome weight should

42:43 Um So the method of warding ford this structure is on a simple structure

42:52 vaccinated but for the moment to infused value where they are not. Then

42:59 also uses the functional again halfway along the access to half of them.

43:11 so they so any curve that goes that takes it to the point,

43:19 follow desperately tangent of X TNX. the point as well as on the

43:27 phone. And then we evaluated the in the morning to then we use

43:37 scope again and for half um same . But now they evaluated us following

43:48 standard against different derivatives and to follow derivative to the very end point and

43:58 gives you another um their ability or . And then you do within your

44:05 of these sports sample the views. But this wait where the two endpoints

44:17 about halfway. You have 25. then it turns out for this particular

44:27 if that's something that has the local area of And that's why it's kind

44:33 the 4th order methods of matches Um terms of the data, serious

44:43 Oh, so yes, wow ! . Yeah, because this was the

44:54 methods and following that, that was other one choose kind of a new

44:59 in terms of the interval. See hope so. And then once occur

45:06 almost up and then we get the at that point and then use that

45:12 to go. So for you to the third Um They're everything that there

45:19 actually three. That is extraordinary. the slope given by K two and

45:27 was mm hmm. 12 hours from And then. four function values.

45:40 what a wonderful thing. Mhm. these guys. And then I went

45:48 Giving the combination of these four So that is what they're Of course

45:56 slide is doing. They would just the point suggested government approximation foursome analytically

46:03 now 4 20 method given their their . Mm hmm. Yeah, that's

46:16 that's charlie's brother. Whether sampling forms in terms of food. So halfway

46:23 10 points. Yeah. So the point and comes from your point.

46:33 those are limited. The space has Donald Trump More than four. Mm

46:43 . Um Right. So this is so can anyone no location matters having

46:57 order message. It's advantageous comparative. in primary something will happen. I

47:08 to start again. It's not totally to compare them directly in terms of

47:19 in the sense of in this case gonna put them happens before. It's

47:23 function evaluations and they're all your Only one. So it's obviously it's

47:29 work. In addition to the linear of us, we should have felt

47:34 that much work but supposed to use normalizes it for the same number of

47:40 evaluations instead of using age in order would take ages before. So that

47:47 the same number of function evaluations as filter method before the accuracy, Eventually

47:56 Manufacturing 16 whereas ages recently small The is you know, 1 16 verses

48:05 skilled and unskilled, a lot less one of his experience. It gives

48:11 much better efforts for the same amount work and that's for them. The

48:19 I want was used before june when look at what I really wanted approximations

48:25 it? That means you get more on this sport. Congratulations for

48:38 Any questions on that. Mhm This is just a good example for

48:57 what kind of so I want to about information from the fact that for

49:16 functions very rapid changes in some things and very still changes in some things

49:23 all. And then they wouldn't, makes sense to use in the tickets

49:29 wants adjusting. Mhm The size and true for all of us as well

49:35 the rapid change not to get largely very small step size, nothing changes

49:48 nor did they economize or work. the kind of some form of transportation

50:02 . So that is the combination of former running back on the airport portal

50:11 another twist on it. Um That's supported for the method and he has

50:21 fish older method and combine those two that's from two years to come up

50:26 something that is good to help So appearance. Another version of something

50:39 is also 4th on the method. , that in this case it's to

50:44 five functional evaluations all by itself. not perfect. That's interesting because now

50:50 is fire function evaluations these guys here we don't get any older methods.

51:00 , but it turns out that if one use this five function about

51:06 one more Then one. In fact 100 organized. And as you can

51:14 from these proficient here and how to things together. It's not entirely trivial

51:19 figure about irregularities now that we have patients you can actually and you can

51:28 it also in the sampling points here very traditional Children. So,

51:37 so now it's absurd. They can one more function evaluation using you previous

51:46 violence. Bye. That disorder method means something that has a local transportation

51:57 . Orange to the sex. How does the prediction of the next

52:05 for this now instead of from the most popular. So mm hmm.

52:20 those things you just flanagan will point of the center for example for this

52:32 a very important and different to the . That's right. I just tried

52:39 did somebody say something. Mm I am born the um,

52:48 Also Jonah. Therefore the So, what that can be used is what

53:03 use is um, I'm gonna cut four or 5 which is moving the

53:09 of before and Also is um, know is the 5th order. Six

53:21 values. And by giving both the and the 5th order blocking the estimates

53:29 error. And then like local error the exhibition and then continue stuff for

53:38 choosing what step size best to use it's fun. Um Sure. Hello

53:54 arrangements here's a gun. The function using these coefficients on this and point

54:03 that's the way they did it this example as well as bye. Um

54:10 an age. Listen Multiplying not for one but it has to be scanned

54:17 the step size stage that has been descriptions. Aah outside here and then

54:25 don't need the native side but then have to take care of it from

54:32 following how they get things the rest it in here. This train one

54:37 that this came of age and the um how far removed And the

54:47 Direction depends on age and that's not them not in front of that is

54:54 here and two um As one of so open. But what this four

55:07 method does is and differences. Um nice fact that that Spielberg version is

55:15 it uses the same Approed 1 2 In the 4th and the 5th quarter

55:25 some of those um I'm not these five conditions, I'm not using differently

55:32 year at long more points. So are actually the very same function.

55:41 open that is You know, those orders including because there's no change in

55:50 . The five points when you want have one more order backwards.

55:57 But if you look at the difference these two estimates based on the fourth

56:02 , the 5th order that gets an of the ever the next part and

56:12 we can use that. So if error is larger than the then you

56:18 redo it with a smaller step sons if there is smaller than you accept

56:27 larger area than what it's being done can increase the steps up. So

56:34 is something this is hardly used then error estimate that we get from using

56:48 both the 4th and the 6th The only additional work is uh for

56:54 both. The fourth and the fifth is you do one more function of

57:01 than yesterday to find a simple expression then that's usually not much of the

57:08 . Most of the work is in function evaluations but we're doing a little

57:13 more extra work and getting the four tom wong. So The only hard

57:23 is usually arguing six. There were doing this linear combination here at that

57:30 . The extra one they do is one, one function of our innocent

57:35 one and the rest of it is trivial in terms of work. So

57:39 get up eric estimates the very little work. In addition to that what

57:53 on has been done with increased series otherwise. But as always should have

58:00 grounds on how large texas and as step sites as well as the number

58:05 steps gone forever. So this is good example. I'll have to do

58:21 . It's a remarkable thing. Mm . Using the area to control the

58:30 . Have some comments on the Wow. So this subject. So

58:48 one so west David says expunging these or in terms of very popular explicit

59:02 from other stuff cover next. Those used very expensive. There's more explicit

59:15 I talked about. Okay. Yeah not talking about that woman or orders

59:26 or five. That's something the racially methods are supported. Yeah, I

59:37 have any but this is hold down workforce methods to song. Thank you

59:57 usually separation would approximation order that the is from you know these remember,

60:14 thanks their analysis And then also we talked about so again This one is

60:33 today's um coming back to it again terms of their analysis, remember this

60:40 finding is showing solution effects and all methods talking about don't um yeah,

60:54 in this case it's kind of exponentially and as we know that investments ah

61:01 changes in restoring point because of external . The difference between the cars grows

61:08 a goal and depending upon signing our error as in the argument that they

61:15 always to go and make a struggle growth on the Memphis unable to shoot

61:20 understood something. But it's still a in that area between whatever you want

61:28 the numerical solution growth. The next . That's a little bit Analysis on

61:37 points and this show on the 5th another negative exponents. I'm sorry.

61:45 they are referenced tickets. That's Huh? So there's a couple of

61:54 interested to figure out. I want son um convinced myself what if things

62:05 exponentially growing and the era of the technologies suspect. Yeah. What the

62:14 . That could be a small change time. This small chance gets

62:20 making this resort and what has been . I think outside it. Just

62:26 to prove it. And then on outside. Mhm. First this was

62:34 differential questions in the next final Pete for that local sensitivity to inspect

62:42 distance initial conditions. So 100 take driven it is a derivative of the

62:52 on the right hand side. And my comfortable currents here in terms of

62:58 hmm. For basic person and actually and they can send the order of

63:05 not. So that's the one get this case, the derivative since um

63:15 and in fact the derivative with Yes. That one has to protect

63:19 derivative with respect to X. and derivative as perspective. That's the first

63:30 respect to the 2nd organ and And then they riveted on the second

63:34 in respect to its dependence. S then we have also respect to the

63:41 argument in terms of and I was first garden offers the starting conditions tests

63:53 he does not in any way with necessary independence of this. No,

63:58 only thing we have to worry about transportation to make a simple one call

64:09 . Yeah. And one of the this part. Yes. For you

64:19 yeah everybody The movement is this one for teeth among your best of best

64:26 fortune and others exponential the question. from playing with this one when you

64:33 something in solution that looks like this the exponents of this financial is injured

64:41 this function to all the time. nonsense if then derivative. Yeah.

64:55 up to so this derivative here is then unfortunately. Yeah. So it's

65:07 . So Then it is bounded away zero. Continue to choose so they

65:17 Yes, that the relative respect of second argument this here is positive,

65:24 possibility and complex one more question. just if you're shopping for financials for

65:44 can take you the government will send no. So talked about three different

65:56 straightforward use of Tennessee's expansion, It evaluation of derivatives and you can choose

66:02 a number of affirmative one but not you for the accuracy that it needs

66:08 and more during christmas and if you an electric expression and will be

66:15 The then who is an american approximation ? It's not usually a good

66:23 counseling can profiles errors and they use interview staff one the space between where

66:35 are and the next point and I accusing the example points and the weighting

66:41 the southern points then you can go again. The same methods, expensive

66:48 that are whatever order they wanted The third version is too quiet tonight

66:59 the best going back to one of smartest guys. Yeah, next nobody's

67:09 look the solution local solution for the sons in time as using the current

67:18 plus the integral of the right and of the question. So it's been

67:26 . The holy method was best to when this was a constant.

67:32 so that's one way of looking at And the other one what's on the

67:39 side say well is that news? formula mr the unknown is also used

67:50 the right hand side. Someone formula actually solve the problem. So now

68:00 the baths and we looked at development methods, one approach was against a

68:11 sample. Um The function in the and tractors don't actually end points the

68:18 son role. Do we have points version and it points but the whole

68:25 was that within your combination of function . Ah that had a property and

68:32 upon how many functions that we choose is correctly integrated the instagram or if

68:41 was important polynomial of the 1st, and 3rd order we could design depending

68:47 how many sampling points to Maria Again, there's a bunch of function

68:55 besides coefficients for linear combination. That some nice properties in terms of the

69:02 of the next. So now we're to do the same except it was

69:11 different. So I wanted to do Let's get started, 1.3 different in

69:22 of solving the ease compared to this Doing integration of 20. So so

69:32 can be, it doesn't show in formula. So it's a little bit

69:42 talk to me story and start thinking . There is a difference between straight

69:50 Between two points. Yes. It's it's it's I mean it's not the

70:04 , the thing that is different and going to be used in this production

70:09 for solving all we need. And the one, this is basically

70:17 progression to start. That's saying something equals zero and then you want to

70:24 it all the time. So I them a point when you want to

70:31 the local staff, they have a maybe start at zero and evolved and

70:40 I'm going to go from an orbiter whatever time be whatever. 10,

70:48 11. Well, you know you already evaluated things history so you have

70:56 history. So I want to do common ominous feeling. You can use

71:02 you already know what they call a of things in history as well as

71:08 kind of prevention future. So that's scenario compared to integration where your best

71:17 have A. And B. And don't have any trying to do that

71:26 of between and and then you choose ages in order to get sampling

71:34 But now we want to use things this integration will require continue to be

71:42 onward. Oh it is then what coming to say? So the difference

71:51 that at some point obviously not from start you have no history. Ah

72:01 some time we have so this quadratic something different to start them and you

72:09 no history one once you have His dreams from the states, the

72:13 states time T. Then we already evaluate what makes some he might be

72:24 the previous canyon spends over two back back etcetera for something once that.

72:31 in that case from the medication here want to do it where we

72:39 But then we're going to use it your combination or all prior function

72:46 Um two Yeah. Then he has make the process. Mm hmm.

72:56 is best for saying that please honor . Mhm. There's some F.

73:02 the corresponding values of X. So these are known as defining your

73:11 time team. That response I thought the that for gays were unknown and

73:19 just started then figure out how to the weighting of the figure. Thanks

73:26 three plus coach. And that's known this evidence that supports thanks. So

73:39 do you find them? The coefficient then we'll go back to so Not

73:47 do standard interval 0 1. That's many times generic. Nothing when that

73:54 to choose that changes things. But this case we are Until zero in

74:02 case or at this point but then have a bunch of prior Bank one

74:08 there was so that is the a of things from the most recent and

74:15 the back in terms of function by are introduced to approximate this for this

74:28 Amanda probably the integration formula. And order to get this method of the

74:36 order. The point was that you choose um the words properly then if

74:45 integrated up to the starting order, on how many points you choose,

74:53 that should be integrated itself. So next form when you're on the bottom

74:58 just using the memorials. So the so far is the binomial here Our

75:05 formula and up two and -1 if have deadline is one um or endpoints

75:12 the storm. So this is the good one over or um so it

75:20 means thanks Are the arguments are our from zero 2 1 -10 which is

75:31 is here is that this is there's here is simply this one will be

75:39 argument and that shouldn't be true for power Opportunity and runs 1st quarter.

75:53 right. So that was fun just get this our system of the

75:58 And while I don't know what the hand side of the integral is that

76:01 integrated is one of the art. we know but the the left hand

76:07 here is and then system of equations A. Is that function values from

76:19 expression of angiogenic and then it's an salt for seasoning. So this mr

76:27 council reservation or whatever they want to is known. There is no it's

76:32 and we can solve for C. the 4th order. So this is

76:40 of what this smoke them formula does some explicit method. They did not

76:50 the income of one used just the set of values zero and where we

77:00 and we can design decide whichever and on how many points you seriously.

77:06 . And then I was transformed medicine a silent order as well and as

77:13 as performance. So for what's the values should be. And that's when

77:22 time is up. So we'll continue this. So these are one

77:27 It was known as the victor character that are another set of popular methods

77:34 someone. So but the predictor character have an implicit component from that.

77:44 you use this to be a prediction then then they pretend that the prediction

77:50 is what it is. And then find an implicit method to that correction

77:57 next But of that's known as the then it was the director of I'm

78:11 talking about that. Thank you. you. Thank you. Yeah.

78:24 . Mm

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