How can i handle variables like A1, A2,..., An in a loop? in R -

i have 10 different objects: a1, a2, ... a10. need make simple change each variable. such as

a1$x <- a1$x + 1 a2$x <- a2$x + 1 ... a10$x <- a10$x + 1 

and

a1[,'new_x']<-cumprod(a1$x) a2[,'new_x']<-cumprod(a2$x) ... a10[,'new_x']<-cumprod(a10$x) 

i'd shrink these codes using 'for' loop. tried

for(i in 1:10) { ai[,'new_x'] <- cumprod(ai$x) } 

and of course not work. there way make work?

you can use looping approach without first converting objects single list or data frame if use eval() function read objects , assign() function write objects. example:

a1 <- data.frame(x=1:5) a2 <- data.frame(x=2:6) a3 <- data.frame(x=3:7)  for(i in 1:3) {   dfname <- paste0("a", i)   df <- eval(parse(text=dfname))   df$new_x <- cumprod(df$x)   assign(dfname, df) }  a1