KL tracking

This tar file allows one to recreate plots found in paper "Energy tracking in a turbulent channel flow using Karhunen-Loe've analysis" to be submitted to Journal of Fluid Mechanics. After download, detar with command "tar -xzf KL_tracking.tar_2.gz". Go to directory "notebooks" and run both notebooks in Jupyter notebook. Files are created in the "Results" and "Plots" directories similar to tables and plots seen in the paper. Parameters can then be changed to look at different wavenumbers, window size, etc. Version 2: Modified calculation of transfer_in and transfer_out