Question

我是八度音阶的初学者。我创建了一个名为x的5x5矩阵，如下所示

 X=ones(5,5)

我想用（-3，+ 5）替换最后一列（第5列）中的所有内容但是当我给出以下命令时它会出错

 y(:,5)=(-3,+5)

我该如何纠正？

Answer 1

数值数组不能将其他数组存储为元素。您必须使用单元格才能实现目标：

X = num2cell(ones(5));
X(:,5) = {[-3 5]}

X = 
{
  [1,1] =  1
  [2,1] =  1
  [3,1] =  1
  [4,1] =  1
  [5,1] =  1
  [1,2] =  1
  [2,2] =  1
  [3,2] =  1
  [4,2] =  1
  [5,2] =  1
  [1,3] =  1
  [2,3] =  1
  [3,3] =  1
  [4,3] =  1
  [5,3] =  1
  [1,4] =  1
  [2,4] =  1
  [3,4] =  1
  [4,4] =  1
  [5,4] =  1
  [1,5] = -3 5
  [2,5] = -3 5
  [3,5] = -3 5
  [4,5] = -3 5
  [5,5] = -3 5
}

或者，您可以通过连接单元格数组使用两个单独的步骤来构建它：

X = [num2cell(ones(5,4)) repmat({[-3 5]},5,1)]

修改

按照评论中的详细信息：

X = randi([0 1],5); idx = X(:,5) == 1; % build an indexer to the elements equal to 1 in column 5 X = num2cell(X); % convert the matrix into a cell array X(idx,5) = {[-3 5]}; % replace the indexed elements with a vector

替换八度矩阵值

1 个答案: