# MATLAB: Trouble with declaring function output

I created a function for importing data from text files, and then outputting an array of the averages of these data.
data = function importerfiles = dir('*.txt');for i = 1:length(files)    temp = importdata(files(i).name);    radData = temp.data(:,4);    radAvg = mean(radData(~radData==0));    data{i} = radAvg;endend
When I run the code however, I get the error
Error: File: importer.m Line: 1 Column: 8Function definitions are not permitted in this context.
However, defining the function simply as
function importer
and then displaying the final array at the end of the code
...enddataend
shows that my code works otherwise. I am not sure what I did wrong but any help would be greatly appreciated.

• function data = importer