Question

I have a list of 50 data.frame objects and each data.frame object contains 20 rows. I need to exclude a row or a vector at each iteration from each of the data.frame object.

The single iteration may look something like this:

to_exclude <- 0  # 0 will be replaced by the induction variable
training_temp <- lapply(training_data, function(x) {
                                        # Exclude the vector numbered to_exclude
                                        }

Regards

Answer 1

df <- data.frame(x=1:10,y=1:10)

thelist <- list(df,df,df,df)

lapply(thelist, function(x) x[-c(1) ,] )

this will always remove the first row. Is this like what you want, or you want to remove rows based on a value?

This will always exclude the first column:

lapply(thelist, function(x) x[, -c(1) ] )

# because there are only two columns in this example you would probably 
# want to add drop = FALSe e.g.
# lapply(thelist, function(x) x[, -c(1), drop=FALSE ] )

so from your loop value:

remove_this_one <- 10
lapply(thelist, function(x) x[ -c(remove_this_one) ,] )
# remove row 10