7.63 set_reference_particle_output
- type: setup command.
- function: Allows defining a reference set of particle coordinates to which tracked coordinates
will be compared for purposes of optimization.
- sequence: must follow optimization_setup.
- Command syntax, including use of equations and subcommands, is discussed in 7.2.
- Usage notes: The purpose of this command is to allow optimization of a transport system to
produce the same particle distribution as was obtained by tracking through some other system.
For example, one might track a collection of particles through a CWIGGLER or BGGEXP element,
then attempt to match the output particles with a different element or set of elements that
offer faster tracking. In this case, the optimization run must use the same input distribution
as the run that is being matched.
&set_reference_particle_output
STRING match_to = NULL;
double weight[6] = {1, 1, 1, 1, 0, 1};
STRING comparison_mode = NULL;
&end
- match_to — Name of an SDDS file from which a particle distribution will be read. The
coordinates of this distribution will be compared to those from tracking to compute a
contribution to the optimization penalty function.
- weight — Weight to be assigned to each plane. By default, path-length coordinates are not
compared.
- comparison_mode — May be one of “max-ad”, “sum-ad”, and “sum-sqr”, corresponding to
maximum absolute deviation, sum of absolute deviations, and sum of squared deviations. The
default is maximum absolute deviation.