xlswrite是否有局限性？

Question

我正在运行MATLAB R2017a。我正在尝试执行一个将3个字符写入Excel文件的简单程序。当我使用少量值运行程序时，这很好，但是当我将其增加到数百万时，程序将暂停。

有人知道为什么编程会这样暂停吗？

X = []    
filename = 'PopltnFL.xlsx';        
NumTrump = 4617886;    
NumClinton = 4504975;    
NumOther = 297025;    
*% Values for which program runs without puasing*    
% NumTrump = 4;
% NumClinton = 4;
% NumOther = 2;
%
for ii = 1:NumTrump
    X = [X,'T'];
end

for jj = 1:NumClinton
    X = [X,'C'];
end

for kk = 1:NumOther
    X = [X,'O'];
end

X = X';
xlswrite(filename,X)