Introduction to the Modeling and Analysis of Complex Systems

15.5. IMPORTING/EXPORTING NETWORK DATA 317values) file. Place this Python code in the same folder where the data file is located, runit, and you will get a result like Fig. 15.7 3 .JackJillJeffJaneJohnJessJoshFigure 15.7: Visual output of Code 15.14.Looks good. No—wait—there is a problem here. For some reason, there is an extranode without a name (at the top of the network in Fig. 15.7)! What happened? The reasonbecomes clear if you open the CSV file in a text editor, which reveals that the file actuallylooks like this:Code 15.15:John,Jane,JackJess,Josh,JillJack,Jane,Jill,Jeff,Jeff,Jane,Note the commas at the end of the third, fourth, and fifth lines. Many spreadsheet applicationstend to insert these extra commas in order to make the number of columns equalfor all rows. This is why NetworkX thought there would be another node whose name was“” (blank). You can delete those unnecessary commas in the text editor and save the file.Or you could modify the visualization code to remove the nameless node before drawingthe network. Either way, the updated result is shown in Fig. 15.8.3 If you can’t read the data file or get the correct result, it may be because your NetworkX did not recognizeoperating system-specific newline characters in the file (this may occur particularly for Mac users). You canavoid this issue by saving the CSV file in a different mode (e.g., “MS-DOS” mode in Microsoft Excel).