Loop through data frame and variable names

Question

I am looking for a way to automate some diagrams in R using a FOR loop:

dflist <- c(\"dataframe1\", \"dataframe2\", \"dataframe3\", \"dataframe4\")

for (i in         


        

Answer 1

To further add to Beasterfield's answer, it seems like you want to do some number of complex operations on each of the data frames.

It is possible to have complex functions within an apply statement. So where you now have:

for (i in dflist) {
  # Do some complex things
}

This can be translated to:

lapply(dflist, function(df) {
  # Do some complex operations on each data frame, df
  # More steps

  # Make sure the last thing is NULL. The last statement within the function will be
  # returned to lapply, which will try to combine these as a list across all data frames.
  # You don't actually care about this, you just want to run the function.
  NULL
})

A more concrete example using plot:

# Assuming we have a data frame with our points on the x, and y axes,
lapply(dflist, function(df) {
  x2 <- df$x^2
  log_y <- log(df$y)
  plot(x,y)
  NULL
})

You can also write complex functions which take multiple arguments:

lapply(dflist, function(df, arg1, arg2) {
  # Do something on each data.frame, df
  # arg1 == 1, arg2 == 2 (see next line)
}, 1, 2) # extra arguments are passed in here

Hope this helps you out!