# FQHECylinderQuasiholeMatrixElements

FQHECylinderQuasiholeMatrixElements is the analogue of FQHESphereQuasiholeMatrixElements for the cylinder geometry. Its usage and outputs are similar to its sphere counterpart except that it supports ths SMP/parallelization mode.

There are a few specific options. The cylinder geometry can be specified either by its perimeter <math>L_y</math> (using the --cylinder-perimeter option) or its aspect ratio <math>L_y/L_x</math> (using the --ratio option). Unless --cylinder-perimeter is set to a positive number, the aspect ratio is used as the default way to set the geometry.

There is also the possibility to focus on a specific number of particles using the --fix-nbrparticles option. In that case, only the matrix elements involving this specific number of particles and the vacuum are computed. For example,

``$PATHTODIAGHAM/build/FQHE/src/Programs/FQHEOnCylinder/FQHECylinderQuasiholeMatrixElements -l 26 --fix-nbrparticles 7 --cylinder-perimeter 8.0

generates all the matrix elements involving 7 particles on cylinder with 26 flux quanta and a perimeter of <math>L_y=8</math>. The data are stored in a folder named nphi_26_n_7_cylinder_perimeter_8.000000.