The column.filter subpackage defines a
{@link ch.javasoft.metabolic.efm.column.filter.ColumnFilter filter} interface
and implementations representing different filtering strategies to sort out
undesired columns. Common filtering strategies include
{@link ch.javasoft.metabolic.efm.column.filter.FutileCycleColumnFilter
removal of futile cycles} and selection of columns
{@link ch.javasoft.metabolic.efm.column.filter.EnforcedFluxColumnFilter
containing enforced fluxes}.