Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
To use top_n function from dplyr to extract rows based on one column ordered indescending order in R, we can follow the below steps −First of all, create a data frame.Then, use top_n function dplyr package along with arrange and desc function to extract rows based on one column ordered in descending order.ExampleCreate the data frameLet’s create a data frame as shown below −x
To create quantile regression plot with larger width of lines using ggplot2 in R, we can follow the below steps −First of all, create a data frame.Then, use stat_quantile function with size argument and geom_point function of ggplot2 package to create quantile regression plot.ExampleCreate the data frameLet’s create a data frame as shown below −x
To subset a matrix in R by specifying columns that contains NA, we can follow the below steps −First of all, create a matrix with some NAs.Then, use is.na along with subset function to subset the matrix by specifying columns that contains NA.ExampleCreate the matrixLet’s create a matrix as shown below −M
To remove a row from matrix in R by using its name, we can follow the below steps −First of all, create a matrix.Then, add names to rows of the matrix.After that, subset the matrix by deselecting the desired row with negation and single square brackets for subsetting.ExampleCreate the matrixLet’s create a matrix as shown below −M
To remove a column from matrix in R by using its name, we can follow the below steps −First of all, create a matrixThen, add names to columns of the matrix.After that, subset the matrix by deselecting the desired column with negation and single square brackets for subsetting.ExampleCreate the matrixLet’s create a matrix as shown below −M
To find the row total of columns having same name in data.table object in R, we can follow the below steps −First of all, create a data.table 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 data.tableLet’s create a data.table as shown below −library(data.table) DT
To extract the last n values of all elements of a list in R, we can follow the below steps −First of all, create a list.Then, use tail function with sapply function to extract the last n values of all elements in the list.Example 1Create the listLet’s create a list as shown below −List1
To find the row total of columns having same name in R data frame, we can follow the below steps −First of all, create a data frame 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 data frameLet’s create a data frame as shown below −df
To apply two sample t test using a categorical column in R data frame, we can follow the below steps −First of all, create a data frame.Then, use t.test function with categorical column and numerical column linked with ~ sign.ExampleCreate the data frameLet’s create a data frame as shown below −Gender
To create a boxplot of single column in R data frame with column name, we can follow the below steps −First of all, create a data frame with single numerical column and create the boxplot for that column using boxplot function.Then, create the same boxplot with show.names argument set to TRUE.ExampleCreate the boxplotUsing boxplot function to create a boxplot for single column of a data frame as shown below −x