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 Purpose: Computes the 2-particle density in the basis of the SPFs.
 Usage:   twopdens [-f -i -skip -cut -n -s -r -ver -h -?] .

Options : 
 -f FILE : The wavefunction is read from file 
           FILE rather than from ./psi
           The string FILE may be a relative or a full path-name.
 -i DIR  : data is read from directory DIR
 -n step : Compute the 2-particle-density only every step-th output.
 -skip n : Skip the first n WFs when computing the 2-particle-density.
 -cut n  : Consider only the first n WFs when computing the 2-p-density.
 -s  s   : Compute the 2-particle-density only for state s.
 -m1 mm1 : Set the first mode index to mm1.
 -m2 mm2 : Set the second mode index to mm2.
 -noev   : Do not print the eigenvalues.
 -r      : Take the restart file rather than the psi file.
 -ver    : Version information about the program 
 -h      : Print this help text. 
 -?      : Print this help text. 

It is in general useful to pipe the output into less:
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