如何在 MATLAB 中正确使用 screenRect 函数？

Question

当我试图在屏幕上的随机位置显示数字时，我运行以下代码：

% Screen parameters
center = [screenRect(3)/2 screenRect(4)/2)];
[mainwin, screenRect] = Screen(0, 'OpenWindow');

% potential locations to place sequences
nrow = 6; ncolumn = 6; cellsize = 100;
for ncells = 1:nrow*ncolumn
    xnum = (mod(ncells-1, ncolumn)+1)-3.5;
    ynum = ceil(ncells/nrow)-3.5;
    cellcenter(ncells,1) = center(1)+xnum.*cellsize;
    cellcenter(ncells,2) = center(2)+ynum.*cellsize;
end

% randomise position of numbers
cellindex = Shuffle(1:nrow*ncolumn); % randomize the position of the sequences within the grid specified earlier
     itemloc = [cellcenter(cellindex(1),1)-cellsize/2, cellcenter(cellindex(1),2)-cellsize/2, cellcenter(cellindex(1),1)+cellsiz

我收到以下错误：

Unrecognized function or variable 'screenRect'.

Error in First_draft (line 4)
center = [screenRect(3)/2 screenRect(4)/2];

Answer 1

如果你确定你正确安装了toolbox，那么

• 1. 使用Screen 方法返回screenRect 变量。

  • [mainwin, screenRect] = Screen(0, 'OpenWindow');
    

• 1. 然后使用screenRectvariable

  • center = [screenRect(3)/2 screenRect(4)/2];
    

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