Matlab实现香农编码

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%shannon - 对信源编香农编码
%   语法
%       shannon(...)
%   输入参数
%       ... - 信源的概率分布
%           总和为1的正数
%   示例
%       shannon(0.25, 0.25, 0.2, 0.15, 0.1, 0.05)
%# ok<*NOPRT>
function shannon(varargin)
    probabilities = sort(cell2mat(varargin), 'descend')
    prefix_sum = [0, cumsum(probabilities(1 : end - 1))]
    code_length = -floor(log2(probabilities))
    extractAfter(string(dec2bin(prefix_sum .* 2 .^ code_length))', max(code_length) - code_length)
end
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