Matrix dimension must agree error

• >> Data1 = 0
• >> spreadcodefor1 = [1 1 1 1 0 0 0 0 1 1 1 1 0 0 0 0];
• >> result1 = xor(Data1,spreadcodefor1);
• >> Data2 = 1
• >> spreadcodefor2 = [1 1 0 0 0 0 1 1 0 0 1 1 1 1 0 0];
• >> result2 = xor(Data2,spreadcodefor2);
• >> allresult = result1 + result2;
• >> SNR = 7;
• >> Noise(1:48) = SNR * rand(1,1);
• >> allnoise = allresult + Noise;

the last statement shows error saying matrix dimensions must agree. I do not know why is this happening. Kindly help

Answer 1

[Guillaume]

I do not know why is this happening

Allresult is 1x16, Noise is 1x48(assuming it didn't exist before you create it). Of course, at the error message tells you, you can't add vectors of different size.

It's really unclear why you create a noise vector with 48 elements.

Noise = rand(size(allresult)) * SNR;

would ensure that Noise always has as many elements as allresult.