Is there a way to fill a column in one Dataframe with a column from a second Dataframe?-CodePudding

Objective: to fill the value of a column in 1 Dataframe from values of a 2nd DF.

I have a Dataframe with the following:

DF1

ID	ValueA	Dates
Aaaaaa	Na	02/13
Bbbbbb	Na	03/13
Cccccc	Na	04/13
Aaaaaa	Na	03/14

DF2

ID	ValueA	Dates
Aaaaaa	12	02/13
Bbbbbb	19	03/13
Aaaaaa	15	03/14
Cccccc	13	04/13

I would like to place ValueA from DF2 into valueA of DF1, with match ID and Dates of each entry without it causing an offset because they may not be in the same order which is the current issue I am getting.

DF1$ValueA <- DF2$ValueA

does not seem to do what I want. I have also tried to fuse to tables with no luck.

Any help of direction would be appreciated. Thanks

CodePudding user response：

Try using dplyr rows_update -

DF1 <- dplyr::rows_update(DF1, DF2, by = c('ID', 'Dates'))
DF1

#      ID ValueA Dates
#1 Aaaaaa     12 02/13
#2 Bbbbbb     19 03/13
#3 Cccccc     13 04/13
#4 Aaaaaa     15 03/14

data

It is easier to help if you provide data in a reproducible format

DF1 <- structure(list(ID = c("Aaaaaa", "Bbbbbb", "Cccccc", "Aaaaaa"), 
    ValueA = c(NA_character_, NA_character_, NA_character_, NA_character_
    ), Dates = c("02/13", "03/13", "04/13", "03/14")), 
   row.names = c(NA, -4L), class = "data.frame")

DF2 <- structure(list(ID = c("Aaaaaa", "Bbbbbb", "Aaaaaa", "Cccccc"), 
    ValueA = c(12L, 19L, 15L, 13L), Dates = c("02/13", "03/13", 
    "03/14", "04/13")), row.names = c(NA, -4L), class = "data.frame")