R Programming Language (Analysis Software for Statistics & Data Science)
R is a programming language and software that is becoming increasingly popular in the disciplines of statistics and data science.
R is a dialect of the S programming language and was developed by Ross Ihaka and Robert Gentleman in the year 1995. A stable beta version was released in the year 2000.
The R software is completely free and gets developed collaboratively by its community (open source software) – every R user can publish new add-on packages.
The open source ideology of R programming reflects a huge contrast compared to most traditional programming environments (e.g. SAS, SPSS, Stata etc.), where the software development is in the hands of a payed development team.
All R Tutorials on statistical-programming.com
In the following, you can find a list of R tutorials on statistical-programming.com. In the tutorials, I’m explaining statistical concepts and provide reproducible example codes in R.
asp in R Plot (2 Example Codes) | Set Aspect Ratio of Scatterplot & Barplot
asp in R Plot (2 Example Codes) | Set Aspect Ratio of Scatterplot & Barplot
In this R tutorial, I'm going to show you how to use the asp option to set the aspect ratio of a plot, i.e. the proportional relationship between width and height...
attach & detach Functions in R | 2 Examples: Data Frame & Package
attach & detach Functions in R | 2 Examples: Data Frame & Package
In this article I will show you how to handle data.frames with the attach and detach functions in R . Let’s start with the basic R syntax and the definition of the two f...
attr, attributes & structure Functions in R | 4 Examples (get, remove & set)
attr, attributes & structure Functions in R | 4 Examples (get, remove & set)
In the following R tutorial, I’m going to show you three functions, with which you can get or set the attributes of your data:
attributes function (Examples 1...
cbind R Command | 3 Example Codes (Data Frame, Vector & Multiple Columns)
cbind R Command | 3 Example Codes (Data Frame, Vector & Multiple Columns)
Basic R Syntax:
cbind(my_data, new_column)
The name of the cbind R function stands for column-bind . The cbind function is used to combine vectors,...
Check if Object is Defined (exists in R) | 4 Examples: Vector, Variable, Function, Error
Check if Object is Defined (exists in R) | 4 Examples: Vector, Variable, Function, Error
In this R tutorial, I'll show you how to check whether a data object exists in your R programming environment. The tutorial is mainly relying on the...
colSums, rowSums, colMeans & rowMeans in R | 5 Example Codes + Video
colSums, rowSums, colMeans & rowMeans in R | 5 Example Codes + Video
In this tutorial, I'll show you how to use four of the most important R functions for descriptive statistics: colSums, rowSums, colMeans, and rowMeans.
I'll explain...
Complete Cases in R (3 Programming Examples)
Complete Cases in R (3 Programming Examples)
A complete data set (i.e. data without any missing values) is essential for many types of data analysis in the programming language R .
In order to deal with missing data , it is crucial to find missing...
Concatenate Vector of Character Strings in R (2 Examples) | How to Combine Text Cases
Concatenate Vector of Character Strings in R (2 Examples) | How to Combine Text Cases
In this article, I’ll explain how to concatenate a vector of character strings in the R programming language . The table of contents is as follows:
Creating E...
Convert Data Frame Column to Numeric in R (2 Examples) | Change Factor, Character & Integer
Convert Data Frame Column to Numeric in R (2 Examples) | Change Factor, Character & Integer
In this R tutorial, I'll explain how to convert a data frame column to numeric in R . No matter if you need to change the class of factors, characters,...
Convert Date to Day of Week in R (3 Examples) | How to Find the Weekday
Convert Date to Day of Week in R (3 Examples) | How to Find the Weekday
In this article, I'll explain how to find the weekday of a date in R . The tutorial is structured as follows
Creation of Example Data in R
Find Weekday...
cumsum R Function Explained (Example for Vector, Data Frame, by Group & Graph)
cumsum R Function Explained (Example for Vector, Data Frame, by Group & Graph)
In many data analyses, it is quite common to calculate the cumulative sum of your variables of interest (i.e. the sum of all values up to a certain position of a vector).
In...
diff Function in R (2 Examples) | How to Calculate the Difference in R
diff Function in R (2 Examples) | How to Calculate the Difference in R
In this article, I'll explain how to calculate differences of a vector with the diff function in R. Let's first have a look at the basic R syntax and the definition...
dir R Function | 3 Example Codes
dir R Function | 3 Example Codes
Basic R Syntax:
dir(path)
The dir R function returns a character vector of file and/or folder names within a directory . The basic syntax for dir in R is illustrated above.
In the following...
Disable Scientific Notation in R (2 Examples) | How to Prevent Exponential Numbers
Disable Scientific Notation in R (2 Examples) | How to Prevent Exponential Numbers
In this tutorial, you will learn how to disable scientific notation (e.g. e+10) in the R programming language . The article will be structured as follows:
Creation...
droplevels R Example | How to Drop Factor Levels of Vector & Data Frame
droplevels R Example | How to Drop Factor Levels of Vector & Data Frame
Basic R Syntax:
droplevels(x)
The droplevels R function removes unused levels of a factor . The function is typically applied to vectors or data frames....
Extract First or Last n Characters from String in R (3 Examples) | Get Leading & Trailing Chars
Extract First or Last n Characters from String in R (3 Examples) | Get Leading & Trailing Chars
In this tutorial, I will explain how to extract n leading or trailing characters from a string in R. I will structure the article as follows:
Creation...
Format Number of Decimal Places in R (2 Example Codes)
Format Number of Decimal Places in R (2 Example Codes)
This tutorial explains how to control the number of decimal places within the R programming language . The table of contents looks as follows:
Creating Example Data
Control...
How to Convert a Character to Numeric in R
How to Convert a Character to Numeric in R
Basic R Syntax:
x_num
require(["mojo/signup-forms/Loader"], function(L) { L.start({"baseUrl":"mc.us18.list-manage.com","uuid":"e21bd5d10aa2be474db535a7b","lid":"841e4c86f0"})...
How to Convert a Factor to Numeric in R
How to Convert a Factor to Numeric in R
Basic R Syntax:
x_num
require(["mojo/signup-forms/Loader"], function(L) { L.start({"baseUrl":"mc.us18.list-manage.com","uuid":"e21bd5d10aa2be474db535a7b","lid":"841e4c86f0"})...
How to Rename a Column Name in R | 3 Examples to Change Colnames of a Data Frame
How to Rename a Column Name in R | 3 Examples to Change Colnames of a Data Frame
Basic R Syntax:
# Change colname of one column
colnames(data)[colnames(data) == "Old_Name"]
Join Data Frames with the R dplyr Package (9 Examples)
Join Data Frames with the R dplyr Package (9 Examples)
In this R programming tutorial, I will show you how to merge data with the join functions of the dplyr package . More precisely, I'm going to explain the following functions:
inner_join...
lowess() R Smoothing Function | 2 Example Codes for Normalization by Lowess Regression
lowess() R Smoothing Function | 2 Example Codes for Normalization by Lowess Regression
Basic R Syntax:
lowess_values
require(["mojo/signup-forms/Loader"], function(L) { L.start({"baseUrl":"mc.us18.list-manage.com","uuid":"e21bd5d10aa2be474db535a7b","lid":"841e4c86f0"})...
NA Omit in R | 3 Example Codes for na.omit (Data Frame, Vector & by Column)
NA Omit in R | 3 Example Codes for na.omit (Data Frame, Vector & by Column)
Basic R Syntax:
na.omit(data)
The na.omit R function removes all incomplete cases of a data object (typically of a data frame, matrix or vector)....
parse, deparse & expression Functions in R | Handle Character String & Expression
parse, deparse & expression Functions in R | Handle Character String & Expression
In this tutorial I will show you how to create expressions , how to convert characters to expressions , and how to convert expressions to characters .
This...
R abs Function (6 Example Codes) | How to Calculate an Absolute Value
R abs Function (6 Example Codes) | How to Calculate an Absolute Value
Basic R Syntax:
abs(x)
The abs R function computes the absolute value of a numeric data object . The basic syntax for abs in R is illustrated above.
In...
R eval Function (3 Examples) | Evaluate Expressions & Character Strings
R eval Function (3 Examples) | Evaluate Expressions & Character Strings
In this R tutorial, I'll explain how to evaluate an expression with the eval function. Let's first have a look at the basic R syntax and the definition of eval:
Basic...
R Find Missing Values (6 Examples for Data Frame, Column & Vector)
R Find Missing Values (6 Examples for Data Frame, Column & Vector)
Let's face it:
Missing values are an issue of almost every raw data set!
If we don't handle our missing data in an appropriate way, our estimates are likely to be biased.
However,...
R Functions List (+ Examples) | All Basic Commands of the R Programming Language
R Functions List (+ Examples) | All Basic Commands of the R Programming Language
List of R Commands & Functions
abs - Compute the absolute value of a numeric data object.
all - Check whether all values of a logical vector...
R is.na Function Example (remove, replace, count, if else, is not NA)
R is.na Function Example (remove, replace, count, if else, is not NA)
Well, I guess it goes without saying that NA values decrease the quality of our data.
Fortunately, the R programming language provides us with a function that helps us to deal...
R max and min Functions | 8 Examples: Remove NA Value, Two Vectors, Column & Row
R max and min Functions | 8 Examples: Remove NA Value, Two Vectors, Column & Row
In this article, you will learn how to use min and max in R. I'm going to explain both functions in the same tutorial, since the R syntax of the two functions...
R NA – What are <Not Available> Values?
R NA – What are <Not Available> Values?
Your data contains NA, <NA>, or NaN values? That's not the end of the world -- but your alarm bells should start ringing!
In R (or R Studio) , NA stands for Not Available . Each cell of your d...
R outer Function | 4 Example Codes (Basic Application & User Defined)
R outer Function | 4 Example Codes (Basic Application & User Defined)
Basic R Syntax:
outer(x, y, "*")
The R outer function applies a function to two arrays . The basic R code for the outer command is shown above.
In...
R pairs & ggpairs Plot Functions | 5 Example Codes (Color, Labels, Panels & by Group)
R pairs & ggpairs Plot Functions | 5 Example Codes (Color, Labels, Panels & by Group)
Basic R Syntax:
pairs(data)
The pairs R function returns a plot matrix, consisting of scatterplots for each variable-combination of a...
R polygon Function | 6 Example Codes (Frequency & Density Plot)
R polygon Function | 6 Example Codes (Frequency & Density Plot)
Basic R Syntax:
polygon(x_coordinates, y_coordinates)
The R polygon function draws a polygon to a plot . The basic R syntax for the polygon command is illustrated...
R pretty Function | 3 Example Codes (Interval Sequence & Set Axis Labels of Plot)
R pretty Function | 3 Example Codes (Interval Sequence & Set Axis Labels of Plot)
Basic R Syntax:
pretty(x)
The pretty R function computes a sequence of equally spaced round values . The basic R syntax for the pretty command...
R Replace Last Comma of Character with &-Sign (5 Examples)
R Replace Last Comma in Character with &-Sign (5 Examples)
If you are working with text data, you will often have a list or enumeration of words that is separated by commas, e.g.:
"Ball, Animal, Beer, Pig, Wagon, Balloon, Hero"
The last comma...
R Replace NA with 0 (10 Examples for Data Frame, Vector & Column)
R Replace NA with 0 (10 Examples for Data Frame, Vector & Column)
A common way to treat missing values in R is to replace NA with 0.
You will find a summary of the most popular approaches in the following.
Choose one of these approaches according...
R scan Function (5 Example Codes) | Read Text or CSV File Line by Line
R scan Function (5 Example Codes) | Read Text or CSV File Line by Line
In this article, I'll explain how to use the scan function to read data into R . Let's first have a look at the basic R syntax and the definition of scan():
Basic...
R sink Function (3 Examples) | Export R output as txt & csv File
R sink Function (3 Examples) | Export R output as txt & csv File
In this article, I'll explain how to use the sink function in R. I'll show you in three examples how to:
print text to a txt file (Example 1)
export data as txt...
R substr & substring Functions | Examples: Remove, Replace, Match in String
R substr & substring Functions | Examples: Remove, Replace, Match in String
In this R tutorial, I'll show you how to apply the substr and substring functions . I'll explain both functions in the same article, since the R syntax and the output...
R sweep Function | 3 Example Codes (Matrix Operation with MARGIN & STATS)
R sweep Function | 3 Example Codes (Matrix Operation with MARGIN & STATS)
Basic R Syntax:
sweep(x = data, MARGIN = 1, STATS = 1, FUN = "+")
The sweep R function applies an operation (e.g. + or -) to a data matrix by row...
R transform Function (2 Example Codes) | Transformation of Data Frames
R transform Function (2 Example Codes) | Transformation of Data Frames
In this tutorial, I'll explain you how to modify data with the transform function. Let's first have a look at the basic R syntax and the definition of the function:
Basic...
R union Function | 3 Example Codes (Two Vectors, Data Frames & Lists)
R union Function | 3 Example Codes (Two Vectors, Data Frames & Lists)
Basic R Syntax:
union(x1, x2)
In R , the union function returns all values that appear in at least one of two data objects (usually vectors). Each value...
R unlist Function | 3 Example Codes (List of Vectors, Data Frame & String)
R unlist Function | 3 Example Codes (List of Vectors, Data Frame & String)
Basic R Syntax:
unlist(my_list)
The unlist R function converts a list to a single vector. The basic code for unlist in R is illustrated above.
In...
rbind in R | 3 Examples (Vector, Data Frame & rbind.fill for Missing Columns)
rbind in R | 3 Examples (Vector, Data Frame & rbind.fill for Missing Columns)
Basic R Syntax:
rbind(my_data, new_row)
The name of the rbind R function stands for row-bind . The rbind function can be used to combine several...
readLines, n.readLines & readline in R (6 Example Codes)
readLines, n.readLines & readline in R (6 Example Codes)
In this tutorial, I’m going to show you how to read text by line with three different R functions :
readLines (Examples 1-4)
n.readLines (Example 5)
readline (Example 6)
...
Remove Element from List in R (7 Example Codes) | How to Delete a List Component
Remove Element from List in R (7 Example Codes) | How to Delete a List Component
In this tutorial, I will show you how to remove one or multiple elements from a list in R . The article is structured as follows:
Creating an Example...
rev R Function | 3 Examples (Reverse of Vector, Data Frame by Column & by Row)
rev R Function | 3 Examples (Reverse of Vector, Data Frame by Column & by Row)
Basic R Syntax:
rev(x)
The rev R function returns a reversed version of a vector or other data objects . The basic R code for the rev command...
setNames vs. setnames in R (+ Examples) | stats & data.table Package
setNames vs. setnames in R (+ Examples) | stats & data.table Package
In this R tutorial, I'll show you how to apply the setNames function of the R package stats and the setnames function of the R package data.table. The two functions are...
Square Root in R (5 Examples) | Apply sqrt Function in R Studio
Square Root in R (5 Examples) | Apply sqrt Function in R Studio
In this tutorial, I'm going to show you how to calculate the square root in R . The tutorial is mainly based on the sqrt function:
Basic R Syntax:
sqrt(x)...
strptime & strftime in R | 5 Example Codes (How to Set Year, Day, Hour & Time Zone)
strptime & strftime in R | 5 Example Codes (How to Set Year, Day, Hour & Time Zone)
In this article, I’ll explain how to convert characters to time objects (and the other way around). The tutorial is based on two R functions:
strptime f...
The all & any R Functions | 4 Example Codes
The all & any R Functions | 4 Example Codes
In this tutorial, I'll show you how to use the all and any R functions. I'm going to combine both functions in this article, since the R syntax and the usage of the two functions are basically...
The difftime R Function | 3 Examples (Return Time Difference in Days, Seconds or Weeks)
The difftime R Function | 3 Examples (Return Time Difference in Days, Seconds or Weeks)
Basic R Syntax:
difftime(time_1, time_2)
The difftime R function calculates the time difference of two date or time objects . The...
The dim Function in R (4 Examples)
The dim Function in R (4 Examples)
Basic R Syntax:
dim(data)
The dim function of the R programming language returns the dimension (e.g. the number of columns and rows) of a matrix, array or data frame. Above, you can see...
The get Function in R (5 Examples)
The get Function in R (5 Examples)
In this article, I'll show you how to use the get function in R . Let's first have a look at the basic R syntax and the definition of the get function:
Basic R Syntax:
get("x")
Definition:...
The is.null Function in R (4 Examples)
The is.null Function in R (4 Examples)
Basic R Syntax:
is.null(x)
The R function is.null indicates whether a data object is of the data type NULL (i.e. a missing value). The function returns TRUE in case of a NULL object...
The jitter R Function | 3 Example Codes (Basic Application & Boxplot Visualization)
The jitter R Function | 3 Example Codes (Basic Application & Boxplot Visualization)
Basic R Syntax:
jitter(x)
The jitter R function adds noise to a numeric vector . Typically, this numeric vector is censored or rounded...
The length Function in R (3 Examples for Vector, List & String)
The length Function in R (3 Examples for Vector, List & String)
Basic R Syntax:
length(x)
The length function returns the length of R objects such as vectors, lists, or strings (find a little trick in Example 3). The R...
The nchar R Function | 3 Examples (String, Vector & Error: nchar Requires a Character)
The nchar R Function | 3 Examples (String, Vector & Error: nchar Requires a Character)
Basic R Syntax:
nchar(x)
The nchar R function counts the number of elements (e.g. letters) of a character object. The basic syntax...
The ncol Function in R (3 Examples)
The ncol Function in R (3 Examples)
Basic R Syntax:
ncol(data)
The ncol R function returns the number of columns of a matrix or data frame. Above, you can find the command for the application of ncol in the R programming...
The nrow Function in R (4 Examples)
The nrow Function in R (4 Examples)
Basic R Syntax:
nrow(data)
The nrow R function returns the number of rows that are present in a data frame or matrix. Above, you can find the R code for the usage of nrow in R.
You...
The pmax and pmin R Functions | 3 Examples (How to Handle Warnings & NA)
The pmax and pmin R Functions | 3 Examples (How to Handle Warnings & NA)
In this tutorial, I will show you how to use the R functions pmax() and pmin() . I'll explain both functions in the same article, since the R syntax of the two functions...
The segments R Function | 3 Example Codes
The segments R Function | 3 Example Codes
Basic R Syntax:
segments(x0 = 1, y0 = 1, x1 = 2, y1 = 2)
The segments R function draws a line segment between two pairs of points . The basic syntax for segments in R is shown above.
In...
The setdiff R Function (3 Example Codes)
The setdiff R Function (3 Example Codes)
Basic R Syntax:
setdiff(x, y)
The R function setdiff indicates which elements of a vector or data frame X are not existent in a vector or data frame Y. The previous code illustrates...
with & within Functions in R (2 Examples)
with & within Functions in R (2 Examples)
In this R programming tutorial I'll show you how to use the with and within functions to handle data in R. Let's first have a look at the basic R syntax and the definition of with() and within():
Basic...
Write xlsx & xls in R (4 Examples) | How to Export Data from R to Excel File
Write xlsx & xls in R (4 Examples) | How to Export Data from R to Excel File
In this article, I'll explain how to write Excel files in R . The tutorial will be based on the write.xlsx function of the xlsx package . So let's first have a...
The Increasing Popularity of R Programming
Since the R programming language provides features for almost all statistical tasks without any costs for the user, R is rapidly growing since its release. Let’s check some numbers…
Graphic 1: Google Scholar Search Results for R Programming Filtered by Year
Reasons to Learn R
The pros:
+ R is free
+ R’s popularity is growing – More and more people will use it
+ Almost all statistical methods are available in R
+ New methods are implemented in add-on packages quickly
+ Algorithms for packages and functions are publicly available (transparency and reproducibility)
+ R provides a huge variety of graphical outputs
+ R is very flexible – Essentially everything can be modified for your personal needs
+ R is compatible with all operating systems (e.g. Windows, MAC, or Linux)
+ R has a huge community that is organized in forums to help each other (e.g. stackoverflow)
+ R is fun 🙂
The cons:
– Relatively high learning burden at the beginning (even though it’s worth it)
– No systematic validation of new packages and functions
– No company in the background that takes responsibility for errors in the code (this is especially important for public institutes)
– R is almost exclusively based on programming (no extensive drop-down menus such as in SPSS)
– R can have problems with computationally intensive tasks (only important for advanced users)
You are not sure yet, whether you should learn the R programming language? In that case, I can recommend the following video of the YouTube channel RenegadeThinking. The speaker provides you with many reasons, why it is advisable to learn R.
Appendix
Appendix 1: R code for the creation of Graphic 1
year <- 2018:2000 # Years r_gs <- c(21600 * 2, 43300, 43100, 38100, 33200, 29800, # Google Scholar searches 28500, 25500, 22400, 19100, 15900, 12000, 8270, 5930, 3740, 2600, 1980, 1600, 1360) data <- data.frame(software = rep("R", 19), # Combine data year = year, searches = r_gs) ggplot(data) + # Create plot geom_point(aes(x = year, y = searches, color = software, shape = software)) + geom_line(aes(x = year, y = searches, color = software)) + theme(legend.title = element_blank(), legend.position = "none") + ggtitle("Google Scholar Search Results") + labs(x = "Year", y = "Search Results") + scale_y_continuous(labels = comma) |
Appendix 2: How to create the header graphic of this page
par(mar = c(0, 0, 0, 0)) # Remove space around plot par(bg = "#1b98e0") # Set background color set.seed(10293847) # Seed N <- 100000 # Sample size x <- rnorm(N) # X variable y <- rnorm(N) + x # Correlated Y variable plot(x, y, col = "#353436", pch = 19, cex = 0.1 # Create plot , xlim = c(- 4, 4), ylim = c(- 7, 7)) text(0, 0, "R", col = "#1b98e0", cex = 12) # Write R points(0, 0, col = "#1b98e0", cex = 30, lwd = 5) # Create circles points(0, 0, col = "#1b98e0", cex = 50, lwd = 5) points(0, 0, col = "#1b98e0", cex = 70, lwd = 5) points(0, 0, col = "#1b98e0", cex = 90, lwd = 5) points(0, 0, col = "#1b98e0", cex = 110, lwd = 5) box(col="#1b98e0") # Color of box |