Creating a Prompt/Answer system to input data into R

Question

I've created some R code for use by people who know nothing of R (though I'm pretty green myself). I've been having people paste in the initial data to the R console (with mixed results), and I was hoping to set up a more user friendly way for people to enter in data.

Ideally someone could sit down at the console, type in a command, and be prompted with specific questions on how to enter the data.

For example, a person loads up r and sees a prompt:

What is x value? 

The person types in:

2 

Next prompt:

What is y value? 

Person types in:

3 

Next prompt:

 What are T values? 

Person types in:

 4,3,2,1 

Next prompt:

What are V values?

Person types in :

4,5,6,9 

And with these 4 newly defined variables (X,Y,T,V) R's next step is to run the pre-written code

X+Y V+T 

And in the console the answers pop up

5 8 8 8 10 

And everyone is happy

My apologies as this is not a reproducible code kind of question, but I'm not sure how to approach making R ask questions as opposed to me asking question about R!

Answer 1

Since this is supposed to be used as interactive code only, readline() can work for you. I did not add any error checking, but you'd probably want to do a fair amount of that to ensure proper input. Here's the core concept though:

fun <- function(){   x <- readline("What is the value of x?")     y <- readline("What is the value of y?")   t <- readline("What are the T values?")   v <- readline("What are the V values?")    x <- as.numeric(unlist(strsplit(x, ",")))   y <- as.numeric(unlist(strsplit(y, ",")))   t <- as.numeric(unlist(strsplit(t, ",")))   v <- as.numeric(unlist(strsplit(v, ",")))    out1 <- x + y   out2 <- t + v    return(list(out1, out2))  } 

Answer 2

See also ?menu from utils for a simple text base menu interface and prompt, which is also used in devtools.

Here is an example:

> menu(c("Yes", "No"), title="Do you want this?") Do you want this?   1: Yes 2: No  Selection: