General R-functions used in a variety of scripts
Function to filter a dataset against a list
From http://www.cookbook-r.com/Manipulating_data/Comparing_data_frames/ function to compare two datasets against each other. Datasets need to have identical column names and merged with an additional column defining the two datasets e.g. column 'df' with dataset 1 having value 'new' and dataset 2 having value 'old' in this column.
Calculate the standard error of the mean for x