I want to create a subset of a dataframe by filtering. With my code, no rows are filtered (plotdata has 3 rows), unless I change the last "chip_id" variable to 434.
What am I missing?
| name | value | chip_id |
|---|---|---|
| a | 3 | 244 |
| b | 4 | 434 |
| c | 5 | 532 |
chip_id <- 434
analyzed_data <- read.csv("./test.csv",
#colClasses = c("chip_id"="factor", )
)
plotdata <- analyzed_data %>% filter(chip_id == chip_id)
It is all about NSE (non-standard evaluation) it can work if you unquoting your global environment variable ,
library(dplyr , warn.conflicts = FALSE)
analyzed_data <- data.frame(name = c("a" , "b" , "c") ,
value = c(3,4,5) ,
chip_id = c(244 , 434 , 532))
analyzed_data
#> name value chip_id
#> 1 a 3 244
#> 2 b 4 434
#> 3 c 5 532
chip_id <- 434
plotdata <- analyzed_data %>% filter(chip_id == !!chip_id)
plotdata
#> name value chip_id
#> 1 b 4 434
Created on 2022-05-30 by the reprex package (v2.0.1)