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 Purpose: Build and output reduced density from pdensity file.
 Usage  : prhosub [-i -w -n -nw -k -q -g -a -ver -h -?] [mode [state]]

Options : 
 -i FILE : The one particle density is read from file FILE rather
           than from ./pdensity
           The string FILE may be a relative or a full path-name.
 -w      : overwrite enabled.
 -n step : Compute the density only every step-th output.
 -nw     : No weights are employed. Write the "naked" DVR populations.
 -k min max: Write the momentum spectrum for the interval min < p < max.
           If "-k d" is given, default values for min and max will be taken.
 -q pts  : Use the number of pts points for representing the momentum
           spectrum. Default: pts =   501
           This option is ignored, when -k is not given.
 -g      : GNUplot command lines are written to the output file(s).
 -a      : GNUplot is called automatically. (sets "-g").
 -ver    : Version information about the program.
 -h      : Print this help text. 
 -?      : Print this help text. 

 The argument "mode" is the mode for which the reduced density is
 calculated. "state" is the electronic state.
 If an argument is not given, the default value 1 will be taken.
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