
Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
Extract Last Row from List of a Data Frame in R
Suppose we have two frames each having 5 columns that are stored in a list in R and we want to extract the last row from each data frame then we can use the lapply function. For example, if we have a list called LIST that contains the data frames described above then we can extract the last row from each data frame using the command lapply(LIST,tail,1).
Example
Consider the below list of data frames −
> x1<-rpois(20,5) > x2<-rpois(20,5) > df1<-data.frame(x1,x2) > y1<-rnorm(20) > y2<-rnorm(20) > df2<-data.frame(y1,y2) > z1<-runif(20,2,5) > z2<-runif(20,2,5) > df3<-data.frame(z1,z2) > List<-list(df1,df2,df3) > List
Output
[[1]] x1 x2 1 6 5 2 6 5 3 1 6 4 3 7 5 3 2 6 1 5 7 2 4 8 4 9 9 3 7 10 6 4 11 3 3 12 7 6 13 5 4 14 6 3 15 3 7 16 6 3 17 6 4 18 6 2 19 2 5 20 4 2 [[2]] y1 y2 1 -0.122804668 -1.6121924 2 0.368791187 -0.1544747 3 0.609177511 -0.1826137 4 -1.203014907 0.2230573 5 0.635002355 -1.8070089 6 1.859925346 -0.7883239 7 -0.031825058 -0.3458682 8 -2.096244574 0.9227411 9 -1.580421379 1.2784456 10 1.110385489 -0.2452274 11 0.336772170 -0.8106806 12 -0.957564919 0.3096939 13 -0.686361808 -0.9769511 14 -1.828680903 -1.3923749 15 -1.455614755 0.6422880 16 1.300948577 1.3421038 17 -0.002059289 0.3392104 18 0.577102561 0.8994493 19 -0.908456903 0.5898572 20 1.085195168 0.5538230 [[3]] z1 z2 1 2.890933 4.918197 2 3.810215 3.869794 3 4.229115 2.709872 4 2.418676 4.464096 5 3.854820 4.876632 6 4.585025 4.080327 7 2.982565 3.604979 8 3.060728 4.523820 9 3.173745 2.203814 10 2.814365 2.806997 11 3.115635 3.032836 12 3.464063 3.498520 13 4.565387 2.021247 14 3.150363 3.273335 15 3.371670 4.497002 16 3.291873 4.102787 17 2.930217 3.962004 18 4.222483 4.428542 19 4.078323 3.199733 20 2.430997 4.328706
Extracting the last row of data frames in List −
> lapply(List,tail,1)
Output
[[1]] x1 x2 20 4 2 [[2]] y1 y2 20 1.085195 0.553823 [[3]] z1 z2 20 2.430997 4.328706
Advertisements