I would like some help to do a subtraction between the date I choose, which is the `dmda`

variable, and the date in my `df database`

, which in this case is `date1`

.

For example: I chose `dmda`

as 30/06/2021. The dates of `date1`

is always 28/06.

Note that the last line is `ch<-dates[2:7,]`

. I put this 2 because I want to subtract `dmda-date1`

, that is, 30/06 - 28-06 = 2. Therefore, this value of 2 can vary, as it will depend on the day I choose in my `dmda`

variable. How do I do this aumomatically, so that I don't have to keep changing the number right there in the `ch`

variable?

```
library(dplyr)
library(lubridate)
library(tidyverse)
#dataset
df <- structure(
list(date1 = c("2021-06-28","2021-06-28","2021-06-28","2021-06-28","2021-06-28",
"2021-06-28","2021-06-28","2021-06-28","2021-06-28"),
date2 = c("2021-04-02","2021-04-03","2021-04-08","2021-04-09","2021-04-10","2021-06-30","2021-07-01","2021-07-02","2021-07-03"),
Week= c("Friday","Saturday","Thursday","Friday","Saturday","Wednesday","Thursday","Friday","Monday"),
DR01 = c(4,1,4,3,3,4,3,6,5), DR02= c(4,2,6,7,3,2,7,4,3),DR03= c(9,5,4,3,3,2,1,5,5),
DR04 = c(5,4,3,3,6,2,1,9,5),DR05 = c(5,4,5,3,6,2,1,9,4),
DR06 = c(2,4,3,3,5,6,7,8,5),DR07 = c(2,5,4,4,9,4,7,8,5)),
class = "data.frame", row.names = c(NA, -9L))
#Generate graph
dmda<-"2021-06-30"
datas<-df %>%
filter(date2 == ymd(dmda)) %>%
summarize(across(starts_with("DR"), sum)) %>%
pivot_longer(everything(), names_pattern = "DR(.+)", values_to = "val") %>%
mutate(name = as.numeric(name))
ch<-datas[2:7,]
```