使用数字条件替换特定组中的值

Question

I have a sample dataset and code which is as follows:

structure(list(Variable = c(NA, "Continuous", "Cell 1", " ",  " ", " ", NA, "Cell 2", NA, NA, NA, NA, "Cell 3", NA, NA, NA,  NA, "Cell 3", NA, NA, NA, NA), Type = c(NA, NA, "Type 1", "Type 2",  "Type 3", "Type 4", "Other", "Type 1", "Type 2", "Type 3", "Type 4",  "Other", "Type 1", "Type 2", "Type 3", "Type 4", "Other", "Type 1",  "Type 2", "Type 3", "Type 4", "Other"), R = c(NA, NA, "1", "  NA",  "0.23", "0.14", "0.4", "0.4", "  NA", "0.88", "0.32", "0.17",  "1", "  NA", "0.39", "0.24", "0.84", "0.27", "  NA", "0.5", "0.27",  "0.18"), R_event = c(NA, NA, "1", "  NA", "0.67", "0.32", "0.53",  "0.81", "  NA", "0.88", "0.32", "0.36", "1", "  NA", "0.67",  "0.32", "0.84", "0.81", "  NA", "0.67", "0.32", "0.36")), class = "data.frame", row.names = c(NA, 
-22L))

I would like to search the 'R' column and replace the 'R_event' column with "0" if the value in 'R' is > 0.2. However, I would like to do this only for "Type 1" cells and not for the entire dataset. Here is the code that I tried:

Table <- read.csv("~/Desktop/Table.csv", stringsAsFactors = , na.strings = c("N/A", ""))

pacman::p_load(pacman, party, rio, tidyverse) 

Table$Type == "Type 1" %>% Table$R_event[Table$R>=0.2] <- 0

But I received the following error:

Error in Table$Type == "Type 1" %>% Table$R_event[Table$R >= 0.2] <- 0 : 
  could not find function "==<-"

Any suggestions on how I can resolve this issue?

Answer 1

First, I think you should convert your strings like "0.53" to numbers, 0.53. This can be done with Table <- type.convert(Table) . Then, I like a direct replacement method:

# direct replacement
Table[Table$R > 0.2 & Table$Type == "Type 1", "R_event"] <- 0

I see you had a pipe attempt with %>% . If you'd like to use dplyr for this, mutate is the main dplyr function for editing columns:

library(dplyr)
Table <- Table %>%
  mutate(R_event = case_when(
    R > 0.2 & Type == "Type 1" ~ 0,
    TRUE ~ R_event   # in all other cases, leave R_event as-is
  ))