R-通过唯一ID折叠data.frame并生成多个虚拟变量

Question

I'm facing a problem I've been trying to solve for a few days now, and I just can't wrap my head around it. Maybe y'all know of a good solution.

I have a data frame, with approx 3,000,000 rows. There is one crucial ID variable, with approx 200,000 rows. I want to collapse the data.frame to a new data.frame, which only has 1 row for each unique ID variable value.

Furthermore, there are a bunch of variables which are also duplicates whenever ID is a duplicate. Here's an example:

ID    NAME   CAR
42    Bob    Ford
42    Bob    Ford
42    Bob    Ford

However, there are also some variables which vary for a subset of the data frame, which denote specific events or actions taken. Here's an example:

ID    NAME   CAR     ACTION    ACTION_ID
42    Bob    Ford    REFILL    4201
42    Bob    Ford    DELIVER   4202
42    Bob    Ford    REFILL    4203

What I want, is for this to be flattened to 1 row, but with new dummy variables. Let's assume that ACTION has 5 values of interest, REFILL, DELIVER, PARK, PICKUP, PATROL in the ENTIRE original data.frame. Furthermore, the ACTION_ID variable is only relevant to the overall ID, and for every given ID variable, there is a maximum number of 5 unique ACTION_ID values.

What I'd like to have is dummy variables for every possible combination of ACTION and ACTION_ID , which would look something like this

ID    NAME   CAR     REFILL_01    REFILL_02    REFILL_03    REFILL_04    REFILL_05
42    Bob    Ford    TRUE         FALSE        TRUE         NA               NA

DELIVER_01    DELIVER_02    DELIVER_03    DELIVER_04    DELIVER_05
FALSE         TRUE          FALSE         NA            NA

with further dummy variables for PARK_n, PICKUP_n and PATROL_n whereby n=1:5 .

I've tried to achieve this with a number of loops whereby I subset the big data.frame by unique ID and then try to generate the new variables and append them to a new data frame. But this never works consistently. I'd be so so grateful if someone had any kind of idea as to how to make this work!

All the best Nik

Answer 1

I was able to make this work. You will need to write the additional code by hand, but this will solve it for you. I am assuming your dataframe is named "df"

library(dplyr)    
new <- df %>% group_by(ID,NAME) %>% mutate(REFILL_01 =
 ifelse(ACTION=="Refill" & substr(ACTION_ID,4,4) == 1,"TRUE","FALSE"),
 REFILL_02 = ifelse(ACTION=="Refill" & substr(ACTION_ID,4,4) == 2, "TRUE","FALSE"))

This takes the data, groups it by ID and then NAME. And then we start making the dummy variables. I will walk you through the first one. REFILL_01 equals TRUE if both ACTION=Refill and if the ending number of ACTION_ID is a 1. Otherwise, it gets a false. Let me know if this makes sense or if you need any more clarification. You just need to add the other dummy variable you want now. I did the REFILL_01 and REFILL_02 for you.