R - Update Dataframe Values in Shiny R

Question

How can I change the values of B by inputting different values for A with an R Shiny dashboard? The output I would like to get is a different dataframe with the updated values, that I can use for visualizations purposes.

Data

test <- as.data.frame(matrix(c(3,6,7), ncol = 1))
colnames(test) <- "A"
test <- test %>% mutate(B = 2*A,
                        C = 3*B)

I would like to have a R Shiny dashboard that allows me to manually change the values of A and then updates the 'test' df so that the values of B and C are a result of the new values of A.

Can anyone help?

Answer 1

Try this in your shiny dashboard (server section)

test <- reactive({ test %>%  mutate(B=2*A, C=3*B) })

You can access the new columns B and C in the dataframe

test()

and it gets updated every time you change A .