- type: major action command.
- function: compute frequency map from tracking Note that the number of turns tracked is set by the run_control command.
- can use parallel resources (Pelegant)
- Command syntax, including use of equations and subcommands, is discussed in 7.2.

&frequency_map

STRING output = NULL;

double xmin = -0.1;

double xmax = 0.1;

double ymin = 1e-6;

double ymax = 0.1;

double delta_min = 0;

double delta_max = 0;

long nx = 21;

long ny = 21;

long ndelta = 1;

long verbosity = 1;

long include_changes = 0;

long quadratic_spacing = 0;

long full_grid_output = 0;

&end

STRING output = NULL;

double xmin = -0.1;

double xmax = 0.1;

double ymin = 1e-6;

double ymax = 0.1;

double delta_min = 0;

double delta_max = 0;

long nx = 21;

long ny = 21;

long ndelta = 1;

long verbosity = 1;

long include_changes = 0;

long quadratic_spacing = 0;

long full_grid_output = 0;

&end

- output — The (incomplete) name of an SDDS file to send output to. Recommended value: “%s.fma”. For the parallel version, particles will be listed in essentially random order. If needed, sddssort can be used to sort particles by initial coordinates.
- xmin, xmax — Limits of grid of initial x coordinates for tracking.
- ymin, ymax — Limits of grid of initial y coordinates for tracking. ymin should be a small, positive value so that there is some betatron oscillation from which to get the tune.
- delta_min, delta_max — Limits of grid of initial δ coordinates for tracking. Note that particles are not centered around the dispersive closed orbit. Hence, the tracking is appropriate to simulation of dynamics from a touschek scattering event.
- nx — Number of values of x coordinate in the grid.
- ny — Number of values of y coordinate in the grid.
- ndelta — Number of values of δ coordinate in the grid.
- verbosity — If nonzero, prints possibly useful information while running.
- include_changes — If nonzero, then computes not only the tunes, but also the changes in the
tunes. This is expressed in terms of the diffusion, which is defined as
(4) where Δν

_{x}and Δν_{y}are respectively the differences in x and y tunes from the first and second half of the tracking (the total number of turns is equal to the value set in run_setup). The diffusion rate,(5) is also computed. d

_{r}is the more conventional quantity, computed by programs such as TRACY and MAD [53]. - quadratic_spacing — If non-zero, the spacing of points is quadratic rather than linear, thus emphasizing the higher amplitude regions.
- full_grid_output — If non-zero, all grid points are represented in the output file, even if tracking or tune determination failed. This makes it possible to plot with programs (e.g., sddscontour) that require a strictly uniform grid.

global_settings