dplyr::bind_cols (remove the first column while combining several data.frames)

Question

I have around 50 data.frames. They are the results of different simulations

Examples of the data.frames are below

SiteID <- c("Site1", "Site2", "Site3", "Site4", "Site5")
measured_s1 <- c(21:25)
simulated_s1 <- c(22:26)
df <- data.frame(SiteID, measured_s1, simulated_s1)

SiteID <- c("Site1", "Site2", "Site3", "Site4", "Site5")
measured_s2 <- c(21:25)
simulated_s2 <- c(21.5:25.5)
df_s2 <- data.frame(SiteID, measured_s2, simulated_s2)

SiteID <- c("Site1", "Site2", "Site3", "Site4", "Site5")
measured_s3 <- c(21:25)
simulated_s3 <- c(21.2:25.2)
df_s3 <- data.frame(SiteID, measured_s3, simulated_s3)

I want to combine all of them. I did it using bind_cols

dplyr::bind_cols(df, df_s2, df_s3)
      SiteID measured_s1 simulated_s1 SiteID measured_s2 simulated_s2 SiteID measured_s3 simulated_s3
  #1  Site1          21           22  Site1          21         21.5  Site1          21         21.2
  #2  Site2          22           23  Site2          22         22.5  Site2          22         22.2
  #3  Site3          23           24  Site3          23         23.5  Site3          23         23.2
  #4  Site4          24           25  Site4          24         24.5  Site4          24         24.2
  #5  Site5          25           26  Site5          25         25.5  Site5          25         25.2

But it resulted in the SiteID column being repeated more than one time in the final data.frame resulting from bind_cols

Now, this can be fixed by removing the repeated SiteID manually or converting the df, df_s2and df_s3to long data.frame then using full_join by SiteID.

Is there any better way to drop SiteID column while combining the data.frames?

Answer 1

You can put your data frames in a list, and then use Reduce function to join them one by one on the SiteID column:

Reduce(dplyr::full_join, list(df, df_s2, df_s3))

#  SiteID measured_s1 simulated_s1 measured_s2 simulated_s2 measured_s3 simulated_s3
#1  Site1          21           22          21         21.5          21         21.2
#2  Site2          22           23          22         22.5          22         22.2
#3  Site3          23           24          23         23.5          23         23.2
#4  Site4          24           25          24         24.5          24         24.2
#5  Site5          25           26          25         25.5          25         25.2

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Or to avoid the join process, and you are aware that all the data frames are aligned well, you can remove the SiteID column with lapply and then use do.call(bind_cols, ...):

bind_cols(df, do.call(bind_cols, lapply(list(df_s2, df_s3), `[`, -1)))