FQHESphereShowBasis

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FQHESphereShowBasis displays the n-body basis used in DiagHam. For example,

$PATHTODIAGHAM/build/FQHE/src/Programs/FQHEOnSphere/FQHESphereShowBasis -p 7 -l 8 -z 0 --boson

shows the n-body basis for 7 bosons with 8 flux quanta and a total Lz value of zero. Display style uses occupation numbers, leftmost occupation being the corresponding to the one body state with the smallest Lz value). Typical output will look like :

   memory requested for Hilbert space = 2Mo                                                                                                          
   3 0 0 0 1 0 0 0 3                                                                                                                                 
   2 1 0 1 0 0 0 0 3                                                                                                                                 
   2 0 2 0 0 0 0 0 3                                                                                                                                 
   1 2 1 0 0 0 0 0 3                                                                                                                                 
   0 4 0 0 0 0 0 0 3

For fermions, you can just remove the --boson i.e.

$PATHTODIAGHAM/build/FQHE/src/Programs/FQHEOnSphere/FQHESphereShowBasis -p 6 -l 15 -z 0

   memory requested for Hilbert space = 4Mo                                                                                           
   1 1 1 0 0 0 0 0 0 0 0 0 0 1 1 1                                                                                                    
   1 1 0 1 0 0 0 0 0 0 0 0 1 0 1 1                                                                                                    
   1 1 0 0 1 0 0 0 0 0 0 1 0 0 1 1                                                                                                    
   1 0 1 1 0 0 0 0 0 0 0 1 0 0 1 1                                                                                                    
   1 1 0 0 0 1 0 0 0 0 1 0 0 0 1 1                                                                                                    
   1 0 1 0 1 0 0 0 0 0 1 0 0 0 1 1                                                                                                    
   0 1 1 1 0 0 0 0 0 0 1 0 0 0 1 1

This code also handles spinful cases. For example, to consider the case of SU(2) spinfule fermions with a pairing term (i.e. without particle conservation), we just have to type

$PATHTODIAGHAM/build/FQHE/src/Programs/FQHEOnSphere/FQHESphereShowBasis --fermion --su2-spin --use-pairing -l 2 -z 0 -s 0

   Hilbert space dimension = 8
   memory requested for Hilbert space = 96
   memory requested for lookup table = 12
   X X X 
   X 0 X 
   d X u 
   d 0 u 
   u X d 
   u 0 d 
   0 X 0 
   0 0 0

Displaying components of a vector in the Fock basis

The code above allows to display all the components of a vector in the given Fock basis. This can be done simply by using the option "--state <vector_filename>" (if the vector is complex, one should also use the option "-c" or "--complex-vector").