This function calculates the statistical performance of all the saved model
runs in the /rswap_saved/ folder, as well as the last performed run. It does
this per variable and for any/all given depths, for the passed
statistical performance indicator stat from package
hydroGOF
Details
The performance indicator will be the result of a function passed as a string
in the stat parameter as called from the hydroGOF package.
The following are supported for stat:
br2 cp d KGE mae md me mNSE mse nrmse NSE pbias rd rmse rNSE rPearson rSD rsr ssq VE
Please note, passing multiple variables at differing depths will not work! (yet)
