How can i reshape a 20370x1 matrix into 2037x10x1?

I have tried to execute this using reshape and permute command.The problem is i am getting either the dimensions as 2037x1x10 or 2037x10. I want the dimension to be 2037x10x1. This is the solution i come up with so far,

>>  r=permute(reshape(modu_data_QAM',2037,10),[2;3;1]);
 The result=    10           1        2037

modu_data_QAM is a matrix of 20370x1 dimension.

Answer 1

[John D'Errico]

MATLAB treats ALL matrices as having essentially an infinite number of trailing singleton dimensions. So a 2x3 matrix is really 2x3x1x1x1x1x1x1... Those trailing singleton dimensions are not reported by size or whos however.

X = zeros(2,3,1,1);
whos X
  Name      Size            Bytes  Class     Attributes

    X         2x3                48  double              

size(X)
ans =
     2     3

However, MATLAB indeed knows that X has trailing singleton dimensions. You can convince yourself of that easily enough.

size(X,3)
ans =
     1

size(X,12)
ans =
     1

Your 2037x10 matrix is indeed a 2037x10x1 matrix. So a simple reshape was all you needed to do.

B = reshape(A,[2037,10]);

[shubhi bhadauria]

Thanks for the reply. Actually i was trying to use the step command for getting a modulated OFDM signal.Thus this error was coming up,that the input should be 2037x10x1. I'll look into my code again> Thanks once again:)

Answer 2

[dpb]

All arrays in Matlab have implied but not explicit unity dimensions in higher dimensions; you can refer to the array with the third subscript explicitly if need to.

Smaller example of same thing...

>> x=rand(200,1);
>> size(x)
ans =
 200     1
>> y=reshape(x,20,10,1);
>> size(y)
ans =
  20    10
>> y(20,10)==y(20,10,1)
ans =
   1
>>

As you can see, referring to the resulting y array with either two or an explicit third (unity) index results in the same thing.

Why do you think you need the explicit third dimension; show us some code snippets of what you're after that can't seem to accomplish (other than just wishing the implicit dimension would show up with size, say).

[shubhi bhadauria]

I understand this now. Thanks for the reply :)