Replace values in data frame column by values of another data frame

Question

I am currently facing the following problem with some housing data. I hava a dataframe which has more than 100,000 observations. For each observation there is a zip code observed. Let's assume the dataframe looks the following

size <- c(20, 30, 40, 50, 30, 45, 60)
rent <- c(100, 200, 300, 400, 350, 460, 700)
ZIP <- c(1000, 1500, 2000, 2500, 1500, 2000, 2500)
df <- data.frame(size, rent, ZIP)

I want to replace the individual zip code levels by other values (build categories on my own). These other values/ categories are stored in anouther data frame that assignes the new value to each zip code level. Say the data frame looks the following:

ZIP_levels <- c(levels(ZIP))
ZIP_New <- c(1, 1, 2, 2)
df2 <- data.frame(ZIP_levels, ZIP_New)

How can I create something like a VLOOKUP that can easily replace the ZIP-values in df with the ZIP_New values out of df2?

`df2$ZIP_New[match(df$ZIP, df2$ZIP)]` or you can try joins using `merge` — Ronak Shah, Jan 05 '19 at 16:45
Just a note, your line `df2 <- (ZIP, ZIP_New)` needs a `data.frame` call to run correctly — Conor Neilson, Jan 05 '19 at 16:50
Thank you @RonakShah. This code helped me to solve my problem! — FJO, Jan 05 '19 at 19:07

score 0 · Answer 1 · answered Jan 05 '19 at 16:47

0

A solution with dplyr

library(dplyr)

df_new <- left_join(df, df2, by = "ZIP")
bf_new$ZIP <- NULL

answered Jan 05 '19 at 16:47

Conor Neilson

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Replace values in data frame column by values of another data frame

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