glmlab allows the user to define link functions and error distributions that are not included with glmlab. This is a more difficult section, and requires some knowledge of vectorised programming in MATLAB. The files dstyle and lstyle give a template for the files to edit, and the files dlist.m and llist.m contain the list of files containing information about the distributions and the links respectively. To demonstrate how to include user-defined distributions in glmlab, see Example 5.7 (the next section).