CODEWITHSUNDEEP
r
jessica
jessica

Reputation: 1355

Merging two vectors into a dataframe by an index

I am trying to comine two data frames such that I match the values in the vectors called vec by their index number. I am looking for an intuitive vlookup function.

    vec=c(-2,-5)
    vec2=c(11,17)
    y1=as.data.frame(cbind(0:(length(c(vec))-1)*2+1,c(vec)))

      V1 V2
    1  1 -2
    2  3 -5

    y2=as.data.frame(cbind(0:(length(c(m$coefficients))-1)*2+2,c(vec2)))

       V1 V2
    1  2 11
    2  4 15

    x=as.data.frame(1:4,names="V1"); names(x)="V1"

      V1
    1  1
    2  2
    3  3
    4  4

What I want is a dataframe to look like this

      V1  V2
    1  1  -2
    2  2  11
    3  3  -5
    4  4  17

So far I was able to do the first merge

c1=merge(x, y1, all.x=TRUE)

  V1 V2
1  1 -2
2  2 NA
3  3 -5
4  4 NA

But unable to do the second with 

c2=merge(c1, y2, all.x=TRUE)

Upvotes: 0

Views: 137

Answers (2)

akrun
akrun

Reputation: 886948

Another option is rbindlist from data.table

library(data.table)
rbindlist(list(y1, y2)[x, on = .(V1)]

Upvotes: 0

Ronak Shah
Ronak Shah

Reputation: 388817

You can rbind y1 and y2 and then merge with x.

merge(x, rbind(y1, y2), by = 'V1')

#  V1 V2
#1  1 -2
#2  2 11
#3  3 -5
#4  4 15

Same logic using dplyr : 

library(dplyr)
bind_rows(y1, y2) %>% inner_join(x, by =  'V1')

Upvotes: 1

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