How to integrate two columns of data in MAT LAB

I have two columns of data in excel and I want to double integrate it in MATLAB using Trapezoidal method. Can some one help me how to do it in MATLAB R2009b. Any help is highly appreciated.

Answer 1

[Wayne King]

Since you are on an older release, how about using dblquad() instead?

[Sathyamoorti]

Yes I do agree but could you please explain me how to integrate discrete datas. I am alien to Matlab

[Jan]

Please explain, what you have tried so far, e.g. if the import from Excel is working already, or if this is a part of the question. Please consider Where to add more details.

[Sathyamoorti]

This is the code which I have tried so far all going futile

function dispdata =  wint(w,dt)
N1=length(w);
numbers = w(1:1001);
N = 2^nextpow2(N1);
if N > N1
w(N1+1:N) = 0;
end
df = 1 / (N*dt); 
Nyq = 1 / (2*dt); 
acc_freq_data = fftshift(fft(w));
disp_freq_data = zeros(size(acc_freq_data));
f = -Nyq:df:Nyq-df; 
for i = 1 : N
if f(i) ~= 0
disp_freq_data(i) = acc_freq_data(i)/(2*pi*f(i)*sqrt(-1))^2;
else
disp_freq_data(i) = 0;
end
end
dispdata = ifft(ifftshift(disp_freq_data));    
dispdata = dispdata(1:N1);

w = xlsread('rawdata1.xlsx'); dt=.02; t=[0:dt:20]; acc = trapz (w,N1); disp = wint(acc,dt); plot(t,disp,t,acc);