Create QQ-Plot with Confidence Interval in R

Nizamuddin Siddiqui
Updated on 06-Feb-2021 11:02:59

3K+ Views

A qqplot is the plot of quantiles that helps to understand whether the supplied data comes from the specified distribution, mostly it is used to check whether the data follows normal distribution or not. If we want to create the qqplot with confidence interval then qqPlot function of car package can be used as shown in the below example.Consider the below data frame −Example Live Demox

Concatenate Numerical Columns in an R Data Frame

Nizamuddin Siddiqui
Updated on 06-Feb-2021 10:59:30

956 Views

If we have values scattered in multiple columns in an R data frame then we need to combine them and create a single column, this combining process is called concatenation. The scatteredness of the values mostly happens when the data is not well formatted to be loaded in R. Therefore, to deal with this scatteredness problem we need to use apply function.Consider the below data frame −Example Live Demox1

Convert Date to Quarter and Year in R

Nizamuddin Siddiqui
Updated on 06-Feb-2021 10:55:21

1K+ Views

Most of the times the date data is available only in date format and there is not information about the quarter of the year. The quarter of the year is required when we want compare the quarters or do some time series analysis. For the conversion of date into quarter and year can be done by using as.yearqtr function from zoo package as shown in the below examples.Examplelibrary(zoo) as.yearqtr("2021-01-19", format="%Y-%m-%d")Output[1] "2021 Q1"as.yearqtr("2021-04-19", format="%Y-%m-%d")[1] "2021 Q2"as.yearqtr(c("2021-04-19", "2020-05-24", "2020-11-09"), format="%Y-%m-%d")[1] "2021 Q2" "2020 Q2" "2020 Q4" Example Live Demox1Read More

Print Vector Elements Vertically in R

Nizamuddin Siddiqui
Updated on 06-Feb-2021 10:53:34

954 Views

By default, the vector elements are printed horizontally in R environment, suppose a vector x has five values then they will be printed as 1, 2, 3, 4, 5. And if we want to print them vertically then the output will be −1 2 3 4 5The printing of these values in vertical form can be done by using the below command −cat(paste(x),sep="")Example Live Demox1

Plot Regression Line Starting from Origin Using ggplot2 in R

Nizamuddin Siddiqui
Updated on 06-Feb-2021 10:50:03

1K+ Views

The regression line starting from origin means that the intercept of the model is dropped from the regression model. To plot the regression line starting from origin, we can use the formula by subtracting 1 in geom_smooth function of ggplot2 package.Consider the below data frame −Example Live Demox

Extract Factor Column Names from an R Data Frame

Nizamuddin Siddiqui
Updated on 06-Feb-2021 10:45:54

1K+ Views

To extract only factor column names from an R data frame, we can use names function with Filter by selecting only factor columns using as.factor. For example, if we have a data frame called df that contains some factor columns then the extraction of names of these factor columns can be done by using names(Filter(is.factor,df)).Consider the below data frame −Example Live Demox1

Display a Line in Segment of a Plot Using ggplot2 in R

Nizamuddin Siddiqui
Updated on 06-Feb-2021 10:39:34

345 Views

To display a line in segment of a plot, we can use geom_segment function of ggplot2 package where we need to pass the initial and the ending values for both the axes. For example, if we have data frame called df that contains x and y then a scatterplot with a line segment can be created by using the below command −ggplot(df,aes(x,y))+geom_point()+ geom_segment(aes(x=xstart,xend=xlast,y=ystart,yend=ylast))Consider the below data frame −Example Live Demox

Find Two-Factor Interaction Variables in R Data Frame

Nizamuddin Siddiqui
Updated on 06-Feb-2021 10:36:44

295 Views

If we have a data frame called df that contains four columns say x, y, z, and a then the two factor interaction columns will be xy, xz, xa, yz, ya, za. To find how many two factor interaction variables can be created using data frame columns, we can make use of combn function as shown in the below examples.Consider the below data frame −Example Live Demox1

Replace 0 in List of Matrices to NA in R

Nizamuddin Siddiqui
Updated on 06-Feb-2021 10:29:55

315 Views

Sometimes missing values are being read as 0 which is not a correct way to represent them, therefore, we must convert the 0’s in the data to NA so that R can understand the difference between missing value and 0’s. For this replacement, we can use lapply function and apply the replacement for all matrices using a function as shown in the below examples.Example Live DemoM1

Save XTable File Locally Using R

Nizamuddin Siddiqui
Updated on 06-Feb-2021 10:25:13

716 Views

To save an xtable file locally, obviously we first need to create the xtable and then use the print function for saving the file. Therefore, we require xtable package loaded in R environment and the data set that we want to save as an xtable file. In the below example, we have used iris data in base R for this purpose. Take a look at the example to understand how it works.Loading xtable package −library(xtable)Considering iris data −Example Live Demodata(iris) head(iris, 20)OutputSepal.Length Sepal.Width Petal.Length Petal.Width   Species 1  5.1           3.5         1.4   ... Read More

Advertisements