![[5 min] Introduction to R
[3 min] How to Install R
[2 min] Installing Packages
[8 min] R Studio GUI & Environment
[10 min] R Basics
[15 min] Example, “Regression to Mean”
2.2](https://image.slidesharecdn.com/introductiontor-r-170518162951/85/Introduction-to-R-r-nabati-iausdj-ac-ir-2-320.jpg)
![> 1550+2000
[1] 3550
or various calculations in the same row
> 2+3; 5*9; 6-6
[1] 5
[1] 45
[1] 0
2.4](https://image.slidesharecdn.com/introductiontor-r-170518162951/85/Introduction-to-R-r-nabati-iausdj-ac-ir-4-320.jpg)
![ NAN (not a number)
NA (missing value)
Basic handling of missing values
> x
[1] 1 2 3 4 5 6 7 8 NA
> mean(x)
[1] NA
> mean(x,na.rm=TRUE)
[1] 4.5
2.5](https://image.slidesharecdn.com/introductiontor-r-170518162951/85/Introduction-to-R-r-nabati-iausdj-ac-ir-5-320.jpg)
![ In R, string variables are defined by double
quotation marks.
> letters
[1] "a" "b" "c"
2.13](https://image.slidesharecdn.com/introductiontor-r-170518162951/85/Introduction-to-R-r-nabati-iausdj-ac-ir-13-320.jpg)
![ Select only one or some of the elements in a
vector, a matrix or an array.
We can do this by using subscripts in square
brackets [ ].
In matrices or dataframes the first subscript
refers to the row and the second to the
column.
2.14](https://image.slidesharecdn.com/introductiontor-r-170518162951/85/Introduction-to-R-r-nabati-iausdj-ac-ir-14-320.jpg)
Introduction to R r.nabati - iausdj.ac.ir
- 1. An Introduction to R:The Basics CE Dep, IAUSDJ.ac.ir 14-02-96(4 April, 2017)
- 2. [5 min] Introduction to R [3 min] How to Install R [2 min] Installing Packages [8 min] R Studio GUI & Environment [10 min] R Basics [15 min] Example, “Regression to Mean” 2.2
- 3. R is object base Types of objects (scalar, vector, matrices and arrays Assignment of objects Building a data frame 2.3
- 4. > 1550+2000 [1] 3550 or various calculations in the same row > 2+3; 5*9; 6-6 [1] 5 [1] 45 [1] 0 2.4
- 5. NAN (not a number) NA (missing value) Basic handling of missing values > x [1] 1 2 3 4 5 6 7 8 NA > mean(x) [1] NA > mean(x,na.rm=TRUE) [1] 4.5 2.5
- 6. Symbol Meaning + Addition - Subtraction * Multiplication / Division %% Modulo (estimates remainder in a division) ^ Exponential &, |, ! Logical And, Or, Not Assign <- <, ==, >, != Lower Than, Equal to, Grater that, Not Equal 2.6
- 7. 2.7 Code Menu-> Run Region-> Run All CTRL+ALT+R
- 8. Objects in R obtain values by assignment. This is achieved by the gets arrow, <-, and not the equal sign, =. NewVersion = works for assign. Objects can be of different kinds. 2.8
- 9. R has many built in functions that compute different statistical procedures. Functions in R are followed by ( ). Inside the parenthesis we write the object (vector, matrix, array, dataframe) to which we want to apply the function. 2.9
- 10. Vectors are variables with one or more values of the same type. A variable with a single value is known as scalar. In R a scalar is a vector of length 1. There are at least three ways to create vectors in R: (a) sequence, (b) concatenation function, and (c) scan function. 2.10
- 11. Arrays are numeric objects with dimension attributes. The difference between a matrix and an array is that arrays have more than two dimensions. 2.11
- 12. A matrix is a two dimensional array. The command colnames 2.12
- 13. In R, string variables are defined by double quotation marks. > letters [1] "a" "b" "c" 2.13
- 14. Select only one or some of the elements in a vector, a matrix or an array. We can do this by using subscripts in square brackets [ ]. In matrices or dataframes the first subscript refers to the row and the second to the column. 2.14
- 15. Researchers work mostly with dataframes . With previous knowledge you can built dataframes in R Also, import dataframes into R. 2.15
- 16. if(cond) expr if(cond) cons.expr else alt.expr Example 1-if(i==0) print(“Yes”) 2- if(i==0) print(“Yes”) else print(“NO”) 2.16
- 17. for(i in 1:5) print(1:i) 2.17
- 18. for(n in c(2,5,10,20,50)) { x <- stats::rnorm(n) cat(n, ": ", sum(x^2), "n", sep = "") } 2.18
- 19. 1st To install R on your MAC or PC you first need to go to http://www.r-project.org Kindly Download & Install R 3.4.0 2nd To Install Rstudio go to https:// www.rstudio.com Simply Download RStudio Desktop Open Source License 2.19
- 20. install.packages(“Package name") library(Library name) CTRL+7 2.20
- 22. igraph, Network Analysis andVisualization dnet, Evaluation and Ontology swirl, Learn R in R You will find all of installed packages at “Package Pane” 2.22
- 23. g <- make_empty_graph(n = 5) %>% add_edges(c(1,2, 2,3, 3,4, 4,5)) %>% 2.23
- 25. 2.25
- 26. Start menu-> All Progtams->Rstudio Click On Rstudio Icon 2.26
- 27. RSeek.org RSeek is a custom search engine that can help you find information on the official website. R-bloggers.com R-Bloggers.com is a blog aggregator of content collected from bloggers who write about R. 2.27
- 28. 2.28
- 32. 2.32
- 34. Thank you for your attention. 2.34
Editor's Notes
- #4: You will learn later that dataframes can be imported from other statistical packages such as Excel and Spss. However, knowing the basics on how R reads dataframes will help you manipulate your own data better in this package.
- #5: To the minimum R can be used as a calculator. The prompt sign means the active line where you are allowed to enter code. The number in brackets is the result. When you enter a line in R, you don’t need to end it with a period as opposed to other software such as the syntax in spss.
- #6: Missing values are noise to statistical estimations. We are going to learn a basic command for handling missing values.
- #10: Talk about useful packages included in the CD.
- #14: In this slide. Go to R code and practice creating objects and vectors.