if (max(m,n) == 1) % 如果wind是标量，则采用长度为此标量值的窗 winsize = wind; if (winsize < 0) winsize = 5; end winsize = winsize - rem(winsize,2) + 1; % 确保窗长必须为奇数 if (winsize > 1) mwind = fix (nfft/winsize); % the scale parameter M lby2 = (winsize - 1)/2; theta = -lby2:lby2; opwind = ones(winsize,1) * (theta .^2); % w(m,n)=m^2 opwind = opwind + opwind' + theta' * theta; % m^2 + n^2 + mn opwind = 1 - (2*mwind/nfft)^2 * opwind; hex = ones(winsize,1) * theta; hex = abs(hex) + abs(hex') + abs(hex+hex'); hex = (hex < winsize); opwind = opwind .* hex; opwind = opwind * (4 * mwind^2) / (7 * pi^2) ; else opwind = 1; end elseif (min(m,n) == 1) % 如果wind为向量，则计算二维窗w(m,n)=w(m)w(n)w(m+n) window = window(:); if (any(imag(window) ~= 0)) disp('1-D window has imaginary components: window ignored') window = 1; end if (any(window < 0)) disp('1-D window has negative components: window ignored') window = 1; end lwind = length(window); windf = [window(lwind:-1:2); window]; % the full symmetric 1-D window = [window; zeros(lwind-1,1)]; opwind = (windf * windf') ... .* hankel(flipud(window), window); % w(m)w(n)w(m+n) winsize = length(window);

这是MATLAB代码中的一个if语句块，用于判断输入的窗口wind是标量还是向量。如果wind是标量，则采用长度为wind的窗口；如果wind是向量，则计算二维窗口。

对于标量情况，代码首先判断winsize是否小于0，如果小于0，则将winsize设为5。然后，代码确保winsize为奇数，并计算得到缩放参数M、卷积核opwind以及窗口hex。最后，计算得到二维窗口opwind。

对于向量情况，代码将输入的窗口向量转化为列向量，并判断其是否有虚部或负数。然后，代码计算得到对应的二维窗口opwind和winsize。