------------------------------------------------------------------------------
 Purpose: Analyses an MCTDH or exact wavefunction in a psi file 
          using diffusion map or isomap methods. Works by sampling gridpoints 
          of the wavefunction at each selected time, locating points where the 
          density is some proportion of the density at the centre of the wavefunction. 
          Selected points are then analysed using eith diffusion map (default) or isomap 
          in order to provide insight into the actual modes which most well describe 
          the dynamics. For more details see Richings and Habershon, Molecules, 2021, 26, 7621.


 Usage  : diffmap [-f -i -stp -n -skip -thrs -thrsmax -thrsmin -ascii -W
                    -abs -abs2 -rst -w -dp -diff -eiso -kiso -eps -k -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 FILE : Same as -f FILE.
 -rst    : A restart file rather than a psi file is read as input.
 -stp step: Compute the exact WF only every step-th output.
 -n num  : only the first num WFs are read  from psi-file.
 -nsample nsample  : number of DVR points sampled  from psi-file. Default is 50.
 -kerscal kerscal  : diffusion length scale.  Default is 1.0.
 -alpha alpha  : diffusion type parameter.  Default is 1.0.
 -eps epsilon  : distance parameter for e-isomap.  Default is 1.0.
 -k kpar  : no. of nearest neighbours for K-isomap.  Default is 1.
 -st st  : state of interest.  Default is 1.
 -skip m : the first m WFs are skipped.
 -random : use random sampling.
 -sobol : use Sobol sampling (default).
 -W      : The DVR-weights are removed from the WF.
           Useful for plotting the WF.
           -W requires that -ort is set, otherwise ignored.
 -thrs thrsmin : The WF and their coordinates are sampled 
           if(abs(WF).GE.thrsmin*abs(WF(centre)). Default 0.2.
 -thrsmin thrsmin : The WF and their coordinates are sampled 
           if(abs(WF).GE.thrsmin*abs(WF(centre)). Default 0.2.
 -thrsmax thrsmax : The WF and their coordinates are sampled 
           if(abs(WF).LE.thrsmax*abs(WF(centre)). Default 1.0.
 -ascii  : The output file is in ascii rather than binary format.
           In this case the (dummy) A-vector and psiinfo 
           are not written, i.e. the file contains the WF only.
 -abs    : The absolute value of the exact WF is written.
           In this case the (dummy) A-vector and psiinfo 
           are not written, i.e. the file contains abs(WF) only.
 -abs2   : Similar to -abs, but the absolute value squared
           of the exact WF is written.
 -dp     : The file is written double precision.
 -diff   : Use diffusion map. (Default).
 -eiso   : Use e-isomap.
 -kiso   : Use K-isomap.
 -w      : An existing output file is overwritten.
 -ver    : Version information about the program 
 -h      : Print this help text. 
 -?      : Print this help text. 
------------------------------------------------------------------------------