Multi tool use

Clash Royale CLAN TAG

How to change the value in a row if condition met in the previous row under dplyr

Is there any alternative way to replace the following codes under dplyr to avoid explicit loop and data name to achieve the following?

This is to create an adjusted date, if the condition of the current supp_date less than the previous supp_date + tablet is met.

test$adj_fill_dt <- as.Date(NA, "%Y-%m-%d")
test$adj_fill_dt[1] <- test$supp_date[1]
for(i in 2:6) {
if (test[i, "supp_date"] < test[i-1, "adj_fill_dt"] + test[i-1, "tablet"]) {
test[i, "adj_fill_dt"] <- test[i-1, "adj_fill_dt"] + test[i-1, "tablet"]
} else {
test[i, "adj_fill_dt"] <- test[i, "supp_date"]
}
}


From:

supp_date tablet
2017-07-19 30
2017-08-07 30
2017-09-08 30
2017-10-11 30
2017-11-08 30
2017-12-07 30


To:

supp_date tablet adj_fill_dt
2017-07-19 30 2017-07-19
2017-08-07 30 2017-08-18
2017-09-08 30 2017-09-17
2017-10-11 30 2017-10-17
2017-11-08 30 2017-11-16
2017-12-07 30 2017-12-16


"target_dose"

tablet

tablet

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