possible bugs in data_analysis_in_python

[cubayang]

Hi Nick,

It seems there are some bugs in the data_analysis folder for python:

1. Line 126: fX_Lag,fY_Lag,fLagMag,fLagNorm,fLagTan = import_Lagrangian_Force_Data(pathForce,numSim) in "Standard_Data_Analysis_Script.py", fLagNorm and fLagTan are no longer used but returned here.
2. Line 104: U,V = read_Eulerian_Data_From_vtk(path,numSim,strChoice,getxy) in "import_Eulerian_Data.py". Should the return values be like "U,V,x,y"?

Thanks,
Yang