how to solve this error horzcat Dimensions of matrices being concatenated are not consistent?

Hi all, how can i solve this error:

t=Tp'; 
dt =t(2)-t(1);
vdrift = filter(d,drift)/dt; 
delay=mean(grpdelay(d))

tt = t(1:end-delay);
vd = vdrift;
vd(1:delay) = [];

tt(1:delay) = [];
vd(1:delay) = [];

[pkp,lcp] = findpeaks(drift); 
zcp = zeros(size(lcp)); 
[pkm,lcm] = findpeaks(-drift); 
zcm = zeros(size(lcm));
figure,plot(t,drift,t([lcp lcm]),[pkp -pkm],'-',"LineWidth",2) 

Error

Values of matrix are:

[Paul Hoffrichter]

Multiple problems.

[lcp lcm] % this expression gives the error you are reporting
[pkp -pkm] % same error
Error using horzcat
Dimensions of arrays being concatenated are not consistent. 

And since the arrays are wrong, it is not clear what your intent is. Did you want to stack lcp over lcm, like this:

a = [lcp; lcm];
length(a)
ans =
        1859

Moving on, the following at least corrects the error message:

plot(t,drift,  t([lcp; lcm]),[pkp; -pkm], '-', "LineWidth", 2);

Answer 1

[Mario Malic]

Hi Miguel,

When you type [var1 var2], you are concatenating horizontally, since your variables have different number of rows, you'll get an error.

This seems troublesome, I don't really understand what are you trying to do here, can you explain?

t([lcp lcm]),[pkp -pkm]

[Miguel Minga]

I'm using this program: Take derivatives of a signal

plot(t([lcp lcm]),[pkp -pkm], 'Marker','x')

When I send to plot that command line I get: the maxima and minima of the drift

[Mario Malic]

plot(t,drift, t(lcp), pkp, t(lcm), -pkm, 'Marker','x');

I am not sure whether this is the proper thing to do, so you should verify yourself

[Miguel Minga]

It works

plot(t,drift, t(lcp), pkp, t(lcm), -pkm, '-')

I use this code to plot

figure
plot(t,drift, t(lcp), pkp, t(lcm), -pkm,'-', 'LineWidth',2)
legend('Input data','Max peak value','Min peak value')
xlabel('Time [s]')
ylabel('Displacement [mamsl]')

And, if I want to graph only the maximum peak value

what would be the code?

[Mario Malic]

Take a look at findpeaks and max in documentation. First one requires Signal Processing Toolbox.

[Miguel Minga]

Thanks Mario

I tried it with this code and it works

figure
plot(t(lcp), pkp,'-', 'LineWidth',2)
legend('Max peak value')
xlabel('Time [s]')
ylabel('Displacement [mamsl]')