Introduction to R

 Introduction for R programming

 The goal of the first part of this book is to get you up to speed with the basic tools of data exploration as quickly as possible. Data exploration is the art of looking at your data, rapidly generating hypotheses, quickly testing them, then repeating again and again and again. The goal of data exploration is to generate many promising leads that you can later explore in more depth.

In this part of the book you will learn some useful tools that have an immediate payoff:

• Visualisation is a great place to start with R programming, because the payoff is so clear: you get to make elegant and informative plots that help you understand data. In data visualisation you’ll dive into visualisation, learning the basic structure of a ggplot2 plot, and powerful techniques for turning data into plots.

• Visualisation alone is typically not enough, so in data transformation you’ll learn the key verbs that allow you to select important variables, filter out key observations, create new variables, and compute summaries.

• Finally, in exploratory data analysis, you’ll combine visualisation and transformation with your curiosity and scepticism to ask and answer interesting questions about data.

Modelling is an important part of the exploratory process, but you don’t have the skills to effectively learn or apply it yet. We’ll come back to it in modelling, once you’re better equipped with more data wrangling and programming tools.

Nestled among these three chapters that teach you the tools of exploration are three chapters that focus on your R workflow. In workflow: basics, workflow: scripts, and workflow: projects you’ll learn good practices for writing and organising your R code. These will set you up for success in the long run, as they’ll give you the tools to stay organised when you tackle real projects.

 My book is about to release. it may contain over 1000 questions. you can contact us to get more information

My data analysis projects.

 

https://www.fiverr.com/s2/6a786172e6https://www.fiverr.com/s2/6a786172e6

Weektask 2 solution of trigonometric equation

 

                                             this was the question I have module there.

It’s pretty much easy to do if you could look at this with a quiet different angle. I have shown each of them by breaking them in to three pieces. This is too difficult to go through usual methods. Usually students use to get some substitution on inverse terms to make them easier. But at this moment those usual substitution just like three of them are going to equal with three different parts such as alpha, bita and gamma will not help you to reach for the solution easily. That’s not impossible but it becomes much more complicate and takes much time. If you pay attention on those angles very carefully you may able to see that right hand side is nothing else the expansion of sin2^n. I have given there pi notation also that is nothing else which stands for the multiplication just like summation. Most appropriate substitution for the right hand side is introduced as mention in calculation. If you are familiar for those plain trigonometrical expressions it’s not too hard to find out it. So keep doing it with them no need to explain others up to final stage coz I’m pretty sure that you may able to complete it now.       It’s pretty much easy to do if you could look at this with a quiet different angle. I have shown each of them by breaking them in to three pieces. This is too difficult to go through usual methods. Usually students use to get some substitution on inverse terms to make them easier. But at this moment those usual substitution just like three of them are going to equal with three different parts such as alpha, bita and gamma will not help you to reach for the solution easily. That’s not impossible but it becomes much more complicate and takes much time. If you pay attention on those angles very carefully you may able to see that right hand side is nothing else the expansion of sin2^n. I have given there pi notation also that is nothing else which stands for the multiplication just like summation. Most appropriate substitution for the right hand side is introduced as mention in calculation. If you are familiar for those plain trigonometrical expressions it’s not too hard to find out it. So keep doing it with them no need to explain others up to final stage coz I’m pretty sure that you may able to complete it now.       

we have started new video series for statistics and probability. you can watch it by clicking on https://youtu.be/Fi8Be2iDbJ8 

Sin rule constant (plain trigonometry )

 In this section i hope to give you an idea about sin rule which is related to plain trigonometry . I have seen that so many students use to call this as a constant but they don't have the proper idea. It should be done even each of every definitions should be known with their geometry. Not only sin rule even we can interpret other geometrical properties of triangles and polygons. Even you guys should be able to derive each of every equations and relationships with geometrical figures. This is shown only for an ordinary triangle but this should be proved for other two sceneries too. Hope you may construct them for others too. That's pretty much easy to derive with projections. Exactly this constant equals to the reciprocal of diameter of it's own circum-circle. It means the constant is unique for the corresponding plain triangle. And also I have tried out to show you how sin ratio can be calculated in terms of sides of triangle. In our old syllabus all these were taught but I would like to ask what happened to them. No need to be framed or trapped in side of a single margin .as well as each of every ratios can be computed. If we could apply s=(a+b+c)/2 expressions can be concluded so far. I just invite you guys to appreciate this. Basic mathematics factors are used. 

Binomial distribution?

 I was busy a little bit with few of my freelancing projects last three days. really sorry for the late answering. Anyway I could see in my website someone has asked to show above expression equals to 'np'. really that's pretty easy to do with the expansion. then you should know the variable here. that's just 'x'. 'x' has been varied from 0 to n. then you guys can keep expanding combinations as shown as above. that's quit different for A/L guys. But you may be taught this exactly once you go ahead furthermore. This is related to a basic stagedy in universe. It doesn't make sense yet but keep this too in your mind thoroughly. Every thing were in old syllabus before 2000. somehow once you recognize that n and p are constants you should be able to take them out. remaining part, you may confused sometimes coz I haven't shown that step there. summation can be separated into two parts as x=0 + form 1 to n. then you may see that x=0 will be dropped simply. so what a familiar expression is this now. are you astonished with it. it was caught simply? yeah that's the binomial expansion of (p+1-p)^n-1. whatever n is, whole part is gonna be equal to 1. that's the law of mother nature, one day you may realize it.

And also I have a kind request for math lovers, please try to understand the reality of integration. https://youtu.be/LMJaZJ69WkI

Integration

Don't forget to share your ideas.

By:SAPUMAL SENADEERAGE SASANKA SAGARA    

Forces along a single plain(Q4)

Today i use to explain it in english coz of some inconvenience with sinhala fonts,anyway i determined  considering this question most of the student had some issues to understand the term 'formed line' it was nothing else when we form a cylinder with a rectangle theres a connection line we use to paste two edges together .so along this form lines A and B cylinders with given measurements then another C cylinder also was given .AB are on C where A touches horizontal  floor.as explained figure was sketched out fairly. All students need to know that you wanna avoid from sketching out special cases. Always try to pay attention on all data you are give then sketch out them with slants fairly .others can be predicted with your knowledge of geometry or calculations based on plane trigonometry .the line which connects A and B is not horizontal .if it doesnt make sense please pay attention on basic trigonometric calculations with projections. Its better to consider M around A considering compound body AB .thats a separated body no more .even theres no reactions between AB so far.If you have any doubt so far please be kind enough to put them here.other questions also may be solved as soon as possible .thank you