r - For Loop to Extract Vector Objects from Dataframe Column Headers -


i have dataframe df 50 columns, , generate vector objects each column name, length of dataframe rows.

my code throws out error:

for in ((1:ncol(df)) {   colnames(df)[i] <- vector(mode = "list", length = nrow(df))   return (colnames(df)[i]) }

the error:

for in ((1:ncol(df)) { error: unexpected symbol in "for i" colnames(df)[i] <- vector(mode = "list", length = nrow(df)) error in colnames(df)[i] <- vector(mode = "list", length = nrow(df)) :
object 'i' not found return (colnames(df)[i]) error: object 'i' not found } error: unexpected '}' in "}"

p.s. of columns in dataframe nested lists, in case affects operation.

for(i in (1:ncol(df)))<----- parenthesis in wrong place


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