Reynolds stress plot error

I'm getting this error when trying to plot this:

Error in BL_9 (line 15)

R = (1./delta) * trapz(y, tau .* u - tau' .* u); % Reynolds stress

not sure how to fix it, any help will be appreciated. thanks

clear all; close all; clc;

U_inf = 100; % free stream velocity in m/s
L = 1; % plate length in m
nu = 1.5e-5; % kinematic viscosity of air in m^2/s
rho = 1.2; % air density in kg/m^3
Re = U_inf * L / nu; % Reynolds number
n = 1/7; % power law exponent for laminar flow

x = linspace(0, 1, 100); % distance from leading edge in m
delta = 5.0 * x / sqrt(Re); % boundary layer thickness
u = U_inf * (x ./ delta).^n; % velocity profile
dudy = n * U_inf ./ delta .* (x ./ delta).^(n-1); % velocity gradient
tau = rho * u .* dudy; % shear stress
R = (1./delta) * trapz(y, tau .* u - tau' .* u); % Reynolds stress

plot(y, R);
xlabel('Distance from leading edge (m)');
ylabel('Reynolds stress (Pa)');
title('Reynolds stress profile');

Answer 1

[VBBV]

clear all; close all; clc;

U_inf = 100; % free stream velocity in m/s
L = 1; % plate length in m
nu = 1.5e-5; % kinematic viscosity of air in m^2/s
rho = 1.2; % air density in kg/m^3
Re = U_inf * L / nu; % Reynolds number
n = 1/7; % power law exponent for laminar flow

x = linspace(0.1, 1, 100); % distance from leading edge in m
delta = 5.0 * x / sqrt(Re); % boundary layer thickness
u = U_inf * (x ./ delta).^n % velocity profile

u = 1×100

244.1008 244.1008 244.1008 244.1008 244.1008 244.1008 244.1008 244.1008 244.1008 244.1008 244.1008 244.1008 244.1008 244.1008 244.1008 244.1008 244.1008 244.1008 244.1008 244.1008 244.1008 244.1008 244.1008 244.1008 244.1008 244.1008 244.1008 244.1008 244.1008 244.1008

dudy = n * U_inf ./ delta .* (x ./ delta).^(n-1); % velocity gradient
tau = rho * u .* dudy % shear stress

tau = 1×100

1.0e+05 * 1.0215 0.9363 0.8643 0.8026 0.7491 0.7023 0.6609 0.6242 0.5914 0.5618 0.5351 0.5107 0.4885 0.4682 0.4494 0.4322 0.4162 0.4013 0.3875 0.3745 0.3625 0.3511 0.3405 0.3305 0.3210 0.3121 0.3037 0.2957 0.2881 0.2809

R = (1./delta).*trapz(x.', tau .* u - tau.' * u) % Reynolds stress

R = 1×100

1.0e+10 * 8.6226 7.0188 5.7875 4.8238 4.0571 3.4384 2.9329 2.5154 2.1672 1.8743 1.6261 1.4142 1.2323 1.0751 0.9386 0.8195 0.7152 0.6234 0.5424 0.4706 0.4068 0.3499 0.2990 0.2535 0.2126 0.1758 0.1426 0.1126 0.0854 0.0608

plot(x, R);
xlabel('Distance from leading edge (m)');
ylabel('Reynolds stress (Pa)');
title('Reynolds stress profile');