Finding the maximum time of ode45

I have a question about my code. I am supposed to find the time at which ymax occurs. I have no idea how to set this up. Thank you.

% Physical constants
m = 45; % kg
l = 10; % m
d = 3.3; % m
rg = 4; % m
I = m*rg^2; % kg.m^2
k = 100e3; % N.m/rad
% Derive the equations of motion and solve them below using ode45

Dz = @(t,z)[z(2);((10*sin(0.1*t)*cos(z(1)*d)-(k/100*(z(1))))/(I+(m*d^2)))];

[t,z] = ode45(Dz,(0:0.1:330),[0;0]);

% Compute the maximum deflection magnitude and the first time of occurence
y = tan(z(:,1)).*l;
ymax = max(abs(y))

tmax = 

[VBBV]

Use the index of the matrix y where the max selection occurs

Answer 1

[Benjamin Großmann]

The max function is able to output the index of the max value:

[ymax, idx_max] = max(abs(y))
tmax = t(idx_max)

[Collin Parker]

Thank you!