I have a cylindrical dipole arrangement and I have run the DDSCAT simulation in online mode with the ddscat.par file having NPLANES=1, in the nanoHUB portal and it's alright but in case of offline mode its showing an error, the output is given below. >  **** Select Elements of S_ij Matrix to Print ****  >REAPAR CMDFRM=TFRAME : scattering directions given in Target Frame  >REAPAR **** Specify Scattered Directions ****  >REAPAR JPBC=0, about to read specs for scattering plane   1  >>>>> FATAL ERROR IN PROCEDURE: REAPAR  >>>>>  Error reading ddscat.par file  >>>>> EXECUTION ABORTED But I can run the offline simulation with NPLANES=0, so I cannot understand its meaning. Please explain this to me and also explain the meaning of NPLANES.