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 Purpose: Converts the wavefunction of a psi file to restart format.
          The argument "step" is the number of the WF to be converted.

 Usage  : psi2rst [-f -i -w  -ver -h -?]  step

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 : The wavefunction is read from file DIR/psi rather than from ./psi
 -o DIR : The output is written to file DIR/restart rather than to ./restart
 -w     : An existing output file is overwritten.
 -ver   : Version information about the program 
 -h     : Print this help text. 
 -?     : Print this help text. 

 NB: The output is written to the file restart in the current directory,
     or to DIR/restart, if the option -o is given.
     To receive some information on the WF file, run "psi2rst nn", where
     nn is zero or a large number (larger than the number of WFs on file).
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