function plan = plate_plan_common(params, P)
% PLATE_PLAN_COMMON  The estimates both plans share.
%
%   plan = plate_plan_common(params, P) fills the fields that do not depend
%   on the method: the plate's mass and the thread's pendulum frequency
%   sqrt(k / m) / (2 pi), the number of modes to expect below f_max from the
%   modal density of a thin plate, n(f) = (A / 2) sqrt(rho h / D) (an
%   asymptotic count; the small plate here has a few more), the Hertz
%   contact estimates and the coincidence frequency.

pl = params.plate;
mu = params.material.rho * pl.thickness;
area = pl.width * pl.height;
density = area / 2 * sqrt(mu / P.D);
plan.plate_mass = P.plate_mass;
plan.thread_k = P.thread_k;
plan.pendulum_hz = sqrt(P.thread_k / P.plate_mass) / (2 * pi);
plan.f_max = P.f_max;
plan.modes_expected = round(density * P.f_max);
plan.modes_cap = params.render.modes;
plan.hertz_duration = P.hertz.duration;
plan.hertz_impulse = P.hertz.impulse;
plan.hertz_peak_force = P.hertz.peak_force;
plan.contact_k = P.hertz.contact_k;
plan.critical_frequency = P.critical_frequency;
plan.nsamples = round(params.render.duration * params.render.fs);
plan.nframes = params.render.nframes;
plan.notes = {};
if P.f_max > 0 && plan.modes_expected == 0
    plan.notes{end + 1} = 'no bending mode is expected below 0.47 fs: raise the sample rate or thin the plate';
end
if plan.modes_expected > params.render.modes
    plan.notes{end + 1} = sprintf('about %d modes below 0.47 fs; only %d are kept (render.modes)', plan.modes_expected, params.render.modes);
end
if params.hammer.speed <= 0
    plan.notes{end + 1} = 'the hammer has no speed: nothing will be struck';
end
end