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In R, multiple data frames can be merged using the “merge” function. This function combines two or more data frames based on a common variable or column. The resulting merged data frame will contain all the rows and columns from the original data frames.
For example, let’s say we have two data frames: “df1” with columns “ID”, “Name”, and “Age” and “df2” with columns “ID”, “Gender”, and “Occupation”. To merge these two data frames based on the “ID” column, we can use the following code:
merged_df <- merge(df1, df2, by = “ID”)
This will create a new data frame “merged_df” with columns “ID”, “Name”, “Age”, “Gender”, and “Occupation”. If there are any matching values in the “ID” column, the corresponding rows from both data frames will be merged into one row in the new data frame.
In addition, the “merge” function also allows for more advanced merging options such as merging based on multiple columns or choosing specific columns to merge. By using this function, multiple data frames can be efficiently merged in R, allowing for easier data analysis and manipulation.
Merge Multiple Data Frames in R (With Examples)
You can use one of the following two methods to merge multiple data frames in R:
Method 1: Use Base R
#put all data frames into list
df_list <- list(df1, df2, df3)
#merge all data frames in list
Reduce(function(x, y) merge(x, y, all=TRUE), df_list)Method 2: Use Tidyverse
library(tidyverse)
#put all data frames into list
df_list <- list(df1, df2, df3)
#merge all data frames in list
df_list %>% reduce(full_join, by='variable_name')
The following examples show how to use each method in practice.
Method 1: Merge Multiple Data Frames Using Base R
Suppose we have the following data frames in R:
#define data frames
df1 <- data.frame(id=c(1, 2, 3, 4, 5),
revenue=c(34, 36, 40, 49, 43))
df2 <- data.frame(id=c(1, 2, 5, 6, 7),
expenses=c(22, 26, 31, 40, 20))
df3 <- data.frame(id=c(1, 2, 4, 5, 7),
profit=c(12, 10, 14, 12, 9))We can use the following syntax to merge all of the data frames using functions from base R:
#put all data frames into list
df_list <- list(df1, df2, df3)
#merge all data frames together
Reduce(function(x, y) merge(x, y, all=TRUE), df_list)
id revenue expenses profit
1 1 34 22 12
2 2 36 26 10
3 3 40 NA NA
4 4 49 NA 14
5 5 43 31 12
6 6 NA 40 NA
7 7 NA 20 9Notice that each of the “id” values from each original data frame is included in the final data frame.
Method 2: Merge Multiple Data Frames Using Tidyverse
Suppose we have the following data frames in R:
#define data frames
df1 <- data.frame(id=c(1, 2, 3, 4, 5),
revenue=c(34, 36, 40, 49, 43))
df2 <- data.frame(id=c(1, 2, 5, 6, 7),
expenses=c(22, 26, 31, 40, 20))
df3 <- data.frame(id=c(1, 2, 4, 5, 7),
profit=c(12, 10, 14, 12, 9))We can use the following syntax to merge all of the data frames using functions from – a collection of packages designed for data science in R:
library(tidyverse)
#put all data frames into list
df_list <- list(df1, df2, df3)
#merge all data frames together
df_list %>% reduce(full_join, by='id')
id revenue expenses profit
1 1 34 22 12
2 2 36 26 10
3 3 40 NA NA
4 4 49 NA 14
5 5 43 31 12
6 6 NA 40 NA
7 7 NA 20 9Note: The tidyverse approach will be noticeably quicker if you’re working with extremely large data frames.
The following tutorials explain how to perform other common functions in R:
Cite this article
stats writer (2024). How can multiple data frames be merged in R? Can you provide examples?. PSYCHOLOGICAL SCALES. Retrieved from https://scales.arabpsychology.com/stats/how-can-multiple-data-frames-be-merged-in-r-can-you-provide-examples/
stats writer. "How can multiple data frames be merged in R? Can you provide examples?." PSYCHOLOGICAL SCALES, 15 May. 2024, https://scales.arabpsychology.com/stats/how-can-multiple-data-frames-be-merged-in-r-can-you-provide-examples/.
stats writer. "How can multiple data frames be merged in R? Can you provide examples?." PSYCHOLOGICAL SCALES, 2024. https://scales.arabpsychology.com/stats/how-can-multiple-data-frames-be-merged-in-r-can-you-provide-examples/.
stats writer (2024) 'How can multiple data frames be merged in R? Can you provide examples?', PSYCHOLOGICAL SCALES. Available at: https://scales.arabpsychology.com/stats/how-can-multiple-data-frames-be-merged-in-r-can-you-provide-examples/.
[1] stats writer, "How can multiple data frames be merged in R? Can you provide examples?," PSYCHOLOGICAL SCALES, vol. X, no. Y, ص Z-Z, May, 2024.
stats writer. How can multiple data frames be merged in R? Can you provide examples?. PSYCHOLOGICAL SCALES. 2024;vol(issue):pages.