made new folder to try writing functions. Have changed means.R to include ie/else statement for extracting months so it can be specified in header
making fn to do all means in one go. must change all 'lon[n]' to 'lon' in previous stepsgit st 'mm' left out as length(start:end) gives right value
need to write baby functions for all steps 1-4, which can then be combined into daddy function to complete step 5. add function names to README file