Furoku 4: Pajek 1.21 eno appu de-to

Translation of title: Appendix 4: Update to Pajek 1.21
Since the publication of this book, Pajek software has been expanded. Additions and changes are listed in the history document (history.htm) that is shown when Pajek is being installed. Most of the changes are self-explanatory or very specialized. Concise explanations are provided in the manual (PajekMan.pdf) which is constantly being updated. The manual can be downloaded from the Pajek website. Some changes, however, are quite fundamental and expand the applications of Pajek considerably even to novice users. In this Appendix, we briefly describe these changes.