Attempted to access key(2,0); index must be a positive integer or logical.

Hello, everyone, i was stuck in one source code line, and i really do not understand how to fix it. here is the source code

[y fs] = wavread('random.wav');

plot(y);

tsamp = 0.01;

t = linspace(0,tsamp,tsamp*fs+1);

M = length(t);

N = floor(length(y)/M);

ys = reshape(y(1:(N*M)),M,N);

fL = [697 770 852 941];

fH = [1209 1336 1477 1633];

omega = 2*pi*fL';

w = exp(1j*omega*t);

yL = abs(w*ys)/M;

plot(yL');

omega = 2*pi*fH';

w = exp(1j*omega*t);

yH = abs(w*ys)/M;

plot(yH');

ndx = 1:4; y1 = ndx*(yL>0.07);

subplot(2,1,1);

plot(y1);

ylabel('low freq index');

subplot(2,1,2);

y2 = ndx*(yH>0.07);

plot(y2);

ylabel('high freq index');

ndx = find(diff(y1)>0);

n1 = y1(ndx+2);

n2 = y2(ndx+2);

[n1' n2']

key = ['147*'; '2580'; '369#'; 'ABCD'];

for k=1:length(n1) pn(k) =key(n2(k),n1(k));

end

disp('phone number:');

disp(pn);

the system says the error is "Attempted to access key(2,0); index must be a positive integer or logical."||

Thanks ~

Answer 1

[Image Analyst]

Your second index to the key array is zero. That's not allowed. I don't know WHY it is zero - we'll let you figure that out, which you can easily do if you know how to use the debugger.

[MU]

hi,thanks for replying, what do you by debugger? Is it a program or a method?

[Image Analyst]

http://blogs.mathworks.com/videos/2012/07/03/debugging-in-matlab/