如何从 Matlab 矩阵中提取一列？

Question

我有以下代码：

N = 10;
params = cell(N-3,4);
step = 1;
for i = 3 : N-1
    
    % Calibrate the camera
    [cameraParams, imagesUsed, estimationErrors] = estimateCameraParameters(imagePoints, worldPoints, ...
        'EstimateSkew', false, 'EstimateTangentialDistortion', false, ...
        'NumRadialDistortionCoefficients', 2, 'WorldUnits', 'centimeters', ...
        'InitialIntrinsicMatrix', [], 'InitialRadialDistortion', [], ...
        'ImageSize', [mrows, ncols]);

    
   %disp(cameraParams.IntrinsicMatrix(1,1));
   %params = [params, cameraParams.IntrinsicMatrix(1,1)];
   params{step} = [cameraParams.IntrinsicMatrix(1,1),...
                      cameraParams.IntrinsicMatrix(2,2),...
                        cameraParams.PrincipalPoint(1),...
                        cameraParams.PrincipalPoint(2)];
                    
   disp(cell2mat(params(step)));
   %disp(cell2mat(cellfun(@(x)   params(:,1),'uniformoutput',false)));
   step = step +1;
   
end

我需要从“params”矩阵中提取每一列（从 1、4 开始）以绘制它们的值...我该怎么做？

当我尝试时：

T = cell2table(params,...
'VariableNames', {'fx', 'fy', 'u0', 'v0'});
disp(T);

我得到：

Answer 1

此处无需将 params 存储在元胞数组中。相反，只需将 params 初始化为包含 NaN 或零的数组。

然后为 params 中的 step 设置适当的行：

N = 10;
params = NaN(N-3,4); % or zeros(N-3,4);
step = 1;
for k = 3 : N-1
    params(step,:) = rand(1,4);
    step = step + 1;
end

T = array2table(params,'VariableNames', {'fx', 'fy', 'u0', 'v0'})

哪个会产生

>> T
T =
  7×4 table
       fx          fy         u0         v0   
    ________    ________    _______    _______
    0.015403    0.043024    0.16899    0.64912
     0.73172     0.64775    0.45092    0.54701
     0.29632     0.74469    0.18896    0.68678
     0.18351     0.36848    0.62562    0.78023
    0.081126     0.92939    0.77571    0.48679
     0.43586     0.44678    0.30635    0.50851
     0.51077     0.81763    0.79483    0.64432

如何从 Matlab 矩阵中提取一列？

How to extract one column from Matlab matrix?

matlab

cell-array