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 Purpose: To selectively plot 1-dimensional densitites.
 Usage  : showd1d [-T|-S|-I|-P|-E|-M|-Ma]
               [-f -i -o -D -a -g -p -x -y -fac -n -no -r -t -skip
              -nofs -l -sm -stick -w -nw -pop2 -G -inter -ver -h -?] fx sx.

Output Formats : 
 -S      : "Step through" by pressing RETURN. (default).
 -M      : "Movie", one picture every second.
 -I id   : "Index file", id=0 shows the first picture, id=1 the second, etc.
 -P pnt  : "Point file", shows the population of the pnt-th grid-point over time.
 -E      : Similar to -P, but shows the population of all grid-point over time.
           May be used to plot state populations of a single-set run.
 -T      : "3D time file" (grid file).
 -Ma     : Mathematica file (for dynamic plots).

Options  : 
 -f FILE : The 1D density is read from file FILE rather than from ./gridpop
           The string FILE may be a relative or a full path-name.
 -i DIR  : Use DIR as name-directory.
 -o FILE : The output is written to file FILE_f* rather than
           to ./den1d_f*
           The string FILE may be a relative or a full path-name.
           If FILE=no, i.e. "-o no", no output file will be opened.
 -D DIR  : The output is written to directory DIR. This is useful,
           if one has no right to write to the name directory.
           The directory DIR must exist.
           The string DIR may be a relative or a full path-name.
 -pop2   : 2nd population plotted (i.e. basis set occupations).
 -g      : GNUplot comand lines are written to the output file(s).
 -a      : GNUplot is called automatically. (sets -g and -w).
 -p      : Print GNUplot (sets -g). Allowed only with -I or -T.
 -sm     : Smooth the plot-data by splines. (Only for GNUplot, sets -g).
 -stick  : Plot sticks rathet than lines. (Only for GNUplot, sets -g).
 -l      : Use logarithmic scale. (Only for GNUplot).
 -n step : Show only every step-th picture. (Only useful for -S, -M).
 -t tfinal : Show densities only up to t=tfinal.
 -skip n : Skip the first n densities.
 -r      : Re-normalize densities.
 -nw     : No weights are employed. Plot the "naked" DVR populations.
 -no     : No output file opened.
 -nofs   : No transformation to fs. Use when 'time-not-fs' was set in mctdh.
 -x xmin xmax : Set the abscissa length (default: auto). Ignored for -T, -Ma.
 -y ymax : Set the upper bound of the ordinate (default: auto). Ignored for -T, -Ma.
 -z ymin : Set the lower bound of the ordinate (default: 0 or 1d-10 (for -l)).
  -x, -y, -z options are ignored when -T or -Ma is set.
 -fac factor : Multiply the density values by factor.
 -G      : Plot gridlines.
 -w      : An existing output file is overwritten.
 -h      : Print this help text. 
 -?      : Print this help text. 
 -ver    : Version information about the program 

 The arguments fx and sx select the dof and state (x=integer).
 With the argument s0 a sum over all states is performed.
 If sx is not to be given, s1 is assumed.
 If no argument is given, the user is prompted for the missing argument.
 EXAMPLES: showd1d -a f1
           showd1d -a -M -y 0.3  -n 2  f2 s1 
           showd1d -w -p -I 20 f1
           showd1d -a -p -T f3
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