Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Physics
Chemistry
Biology
Mathematics
English
Economics
Psychology
Social Studies
Fashion Studies
Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
How to find the column median if some columns are categorical in R data frame?
To find the column median if some columns are categorical in R data frame, we can follow the below steps −
First of all, create a data frame.
Then, use numcolwise function from plyr package to find the column median if some columns are categorical.
Example 1
Create the data frame
Let’s create a data frame as shown below −
Group<-sample(c("I","II","III","IV"),25,replace=TRUE)
Num1<-sample(1:50,25)
Num2<-sample(1:50,25)
df1<-data.frame(Group,Num1,Num2)
df1Output
On executing, the above script generates the below output(this output will vary on your system due to randomization) −
Group Num1 Num2 1 III 46 25 2 I 41 39 3 III 4 1 4 IV 32 23 5 IV 2 7 6 III 7 15 7 II 44 48 8 IV 40 3 9 III 36 45 10 III 45 11 11 II 21 10 12 IV 23 47 13 I 12 35 14 III 3 42 15 IV 43 40 16 IV 19 14 17 IV 15 6 18 I 35 38 19 IV 18 34 20 II 20 44 21 III 30 17 22 IV 34 32 23 II 16 18 24 I 14 5 25 I 13 24
Find the column median if some columns are categorical
Using numcolwise function from plyr package to find the column median of numerical columns in the data frame df1 −
Group<-sample(c(“I”,”II”,”III”,”IV”),25,replace=TRUE) Num1<-sample(1:50,25) Num2<-sample(1:50,25) df1<-data.frame(Group,Num1,Num2) library(plyr) numcolwise(median)(df1)
Output
Num1 Num2 1 30 28
Example 2
Create the data frame
Let’s create a data frame as shown below −
Categories<-sample(c("First","Second","Third"),25,replace=TRUE)
Score<-sample(1:10,25,replace=TRUE)
Price<-sample(1:5,25,replace=TRUE)
df2<-data.frame(Categories,Score,Price)
df2Output
On executing, the above script generates the below output(this output will vary on your system due to randomization) −
Categories Score Price 1 Second 4 3 2 First 2 2 3 Third 4 2 4 Second 2 4 5 Second 4 2 6 First 4 3 7 Third 3 5 8 Third 4 3 9 First 6 1 10 Third 4 1 11 First 5 3 12 Second 8 5 13 Third 4 1 14 Second 5 2 15 Second 6 5 16 Third 7 5 17 Third 6 2 18 Third 3 1 19 Second 1 4 20 Second 7 3 21 Second 4 2 22 Third 4 3 23 Second 1 5 24 First 6 2 25 First 4 3
Find the column median if some columns are categorical
Using numcolwise function from plyr package to find the column median of numerical columns in the data frame df2 −
Categories<-sample(c("First","Second","Third"),25,replace=TRUE)
Score<-sample(1:10,25,replace=TRUE)
Price<-sample(1:5,25,replace=TRUE)
df2<-data.frame(Categories,Score,Price)
library(plyr)
numcolwise(median)(df2)Output
Score Price 1 6 4
116 Views
