R: merge based on multiple conditions (with non-equal criteria)

Question

I would like to merge 2 data frames based on multiple conditions.

DF1 <- data.frame(\"col1\" = rep(c(\"A\",\"B\"), 18),
                  \"col2\" = rep(c         


        

Answer 1

Your data, changing stringsAsFactors=F

DF1 <- data.frame("col1" = rep(c("A","B"), 18),
              "col2" = rep(c("C","D","E"), 12),
              "value"= (sample(1:100,36)),
              "col4" = rep(NA,36),
              stringsAsFactors=F)

DF2 <- data.frame("col1" = rep("A",6),
              "col2" = rep(c("C","D"),3),
              "data" = rep(c(1,3),3),
              "min" = seq(0,59,by=10),
              "max" = seq(10,69,by=10),
              stringsAsFactors=F)

Using dplyr, 1) merge the two data using left_join, 2) check ifelse value is between min and max rowwise, then 3) unselect min and max columns...

library(dplyr)
left_join(DF1, DF2, by=c("col1","col2")) %>%
  rowwise() %>%
  mutate(data = ifelse(between(value,min,max), data, NA)) %>%
  select(-min, -max)

Not sure if you were expecting to perform some kind of aggregation, but here's the output of the above code

    col1  col2 value  col4  data
 1     A     C    23    NA    NA
 2     A     C    23    NA     1
 3     A     C    23    NA    NA
 4     B     D    59    NA    NA
 5     A     E    57    NA    NA
 6     B     C     8    NA    NA