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To find the number of zeros in each row of a data.table object in R, we can follow the below steps −First of all, create a data.table object.Then, use rowSums function to find the number of zeros in each row of the data.table object.ExampleCreate the data.table objectLet’s create a data.table object as shown below −library(data.table) x
To find the percentage of each category in an R data frame column, we can follow the below steps −First of all, create a data frame.Then, use summarise function of dplyr package after grouping along with n and nrow.ExampleCreate the data frameLet’s create a data frame as shown below −Group
To create pivot table with sum for data stored in data.table object in R, we can follow the below steps −First of all, create a data.table object with two categorical and one numerical column.Then, use dcast function from reshape2 package to create pivot table for the data stored in data.table object.ExampleCreate the data.table objectLet’s create a data.table object as shown below −library(data.table) Factor
To find the number of columns where all row values are equal in R data frame, we can follow the below steps −First of all, create a data frame.Then, use sum function along with length and apply function to find the number of columns where all row values are equal.Example 1Create the data frameLet’s create a data frame as shown below −x
To create histogram with varying binwidth using ggplot2 in R, we can follow the below steps −First of all, create a data frame.Then, use geom_histogram function with breaks argument having varying differences.ExampleCreate the data frameLet’s create a data frame as shown below −x
To delete repeated rows in xts object in R, we can follow the below steps −First of all, create an xts object.Then, use duplicated and index function to delete repeated rows.ExampleCreate the xts objectLet’s create an xts object as shown below −library(xts) T
To multiply single row matrix and a square matrix in R, we can follow the below steps −First of all, create the matrices.Then, use %*% to multiply those matrices.ExampleCreate the first matrixLet’s create a matrix as shown below −M1
To display square root sign in base R plot, we can follow the below steps −First of all, create a plot having square root values to display default visualisation.Then, create the plot with expression function to display square root sign in the plot.ExampleCreate plot in base RUsing plot function to create a plot in base R with square root values as shown below −x
To separate a specific text and the remaining text in data.table object column in R, we can follow the below steps −First of all, create a data.table object.Then, use str_split function from stringr package to separate first text value and the remaining text.ExampleCreate the data.table objectLet’s create a data.table object as shown below −library(data.table) Student_ID
To find the row total of columns having same name in R matrix, we can follow the below steps −First of all, create a matrix with some columns having same name.Then, use tapply along with colnames and sum function to find the row total of columns having same name.ExampleCreate the matrixLet’s create a matrix as shown below −M