using num2str for subplot titles

Hello guys

In my code I need to have varying subplot titles like Q1S1, Q1S2 and Q1S3 (respectively for subplot 1 to 3 (first row)) ,I am using the following code but it seems there is some thing missing that I get error: Incorrect number of input arguments

Any Idea what I am missing?

for k=1:3
    subplot(3,3,k)
    plot(Q1S(:,k),depth_z,'.-',A_Q1S(:,k),depth_z,'.',B_Q1S(:,k),depth_z,'o',C_Q1S(:,k),depth_z,'*')
    title('Q1S', num2str(k)) % the output I want is Q1S1, Q1S2 and Q1S3
    xlabel('Velocity($m/s$)','interpreter','latex','fontsize',10);
    ylabel('water depth($m$)','interpreter','latex','fontsize',10);
end

Answer 1

[Alan Stevens]

Try

 title(['Q1S', num2str(k)])

i.e. enclose the two terms within square brackets.