I have an app that displays a data table, in this data table the user can select rows by clicking on them to display in various figures. i want to include a function where the user can input a txt file as a single column list of row names. i then want to convert this txt file to a single column data frame and use the match() function to find the rows in the data table that match the text list. i then want to select the rows that match to display in the figures. i am using the fileInput() option to read in the txt file and i have attempted to manipulate the txt file in the reactive({}) function but that has not worked. any help would be greatly appreciated.