Article Categories
- All Categories
-
Data Structure
-
Networking
-
RDBMS
-
Operating System
-
Java
-
MS Excel
-
iOS
-
HTML
-
CSS
-
Android
-
Python
-
C Programming
-
C++
-
C#
-
MongoDB
-
MySQL
-
Javascript
-
PHP
-
Economics & Finance
Server Side Programming Articles
Page 1148 of 2109
How to create the plots arranged in a list that were generated using ggplot2 in R?
If we have two plots generated by using ggplot2 and arranged in a list then we can create them using ggarrange function. For example, if we have two objects p1 and p2 that are stored in the list called named as LIST then those plots can be created in the plot window by using the command ggarrange(plotlist=LIST,widths=c(2,1),labels=c("Scatter","Hist"))ExampleConsider the below data frame −set.seed(21) x
Read MoreHow to create a sparse matrix in R?
A sparse matrix is a type of matrix that has most of the elements equal to zero but there is no restriction for the number of zero elements. As a general criterion the number of non−zero elements are expected to be equal to the number of rows or number of columns. To create a sparse matrix in R, we can use sparseMatrix function of Matrix package.Example1i
Read MoreHow to replace NA with 0 and other values to 1 in an R data frame column?
Sometimes we want to convert a column of an R data frame to binary column using 0 and 1, it is especially done in situations where we have some NAs in the column of the data frame and the other values can be converted to 1 due to some characteristics. To replace NA with 0 and other values to 1, we can use ifelse function.Example1y1
Read MoreHow to create combinations of 0 and 1 with fixed number of 1s in each row in an R data frame?
To create the combinations of 0 and 1 data frame, we can use expand.grid function along with the rep function. If we want to create combination of 0 and 1 with fixed number of 1’s in each row then rowSums functions can be used with the appropriate sum value. For example, to have rows containing less than three 1’s, the rowSums will be extracted from grid for the same.Example1First
Read MoreHow to remove rows for categorical columns that has three or less combination of duplicates in an R data frame?
In Data Analysis, we sometimes decide the size of the data or sample size based on our thoughts and this might result in removing some part of the data. One such thing could be removing three or less duplicate combinations of categorical columns and it can be done with the help of filter function of dplyr package by grouping with group_by function.Example1y1
Read MoreHow to find the percentage of missing values in an R data frame?
To find the percentage of missing values in an R data frame, we can use sum function with the prod function. For example, if we have a data frame called df that contains some missing values then the percentage of missing values can be calculated by using the command: (sum(is.na(df))/prod(dim(df)))*100Example1y1
Read MoreHow to convert multiple columns into single column in an R data frame?
To convert multiple columns into single column in an R data frame, we can use unlist function. For example, if we have data frame defined as df and contains four columns then the columns of df can be converted into a single by using data.frame(x=unlist(df)).Example1y1
Read MoreHow to count the number of duplicate rows in an R data frame?
To count the number of duplicate rows in an R data frame, we would first need to convert the data frame into a data.table object by using setDT and then count the duplicates with Count function. For example, if we have a data frame called df then the duplicate rows will be counted by using the command − setDT(df)[,list(Count=.N),names(df)].Example1y1
Read MoreHow to create a categorical variable using a data frame column in R?
If a variable is numerical then it can be converted into a categorical variable by defining the lower and upper limits. For example, age starting from 21 and ending at 25 can be converted into a category say 21−25. To convert an R data frame column into a categorical variable, we can use cut function.Example1y1
Read MoreHow to find the counts of categories in categorical columns in an R data frame?
If we have two categorical columns in an R data frame then we can find the frequency/count of each category with respect to each category in the other column. This will help us to compare the frequencies for all categories. To find the counts of categories, we can use table function as shown in the below examples.Example1y1
Read More