You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: TestBasicArray.m
    path of file: ./repos/MatlabStan/Tests
    
    the code of the file until where you have to start completion: % xUnit framework required
% http://www.mathworks.com/matlabce
    
function test_extract_permuted(self)
         fit = self.fit;
         % extract, permuted = true
         beta = fit.extract().beta;
         assertEqual(size(beta),[4000 4 1 2]);
         beta_mean = mean(beta,1);
         assertEqual(size(beta_mean),[1 4 1 2]);
         assertTrue(all(beta_mean(:,1,1) < 4),'Should be < 4 on this dimension');
         assertTrue(all(beta_mean(:,1,2) > (100-4)),'Should be > 100 on this dimension');
      end