from Arithemetic Coding by Ravi Lakkundi
Program to compress text using arithmetic coding.

start_model_adaptive
function start_model_adaptive

format long

global no_of_chars cum_freq no_of_symbols char_to_index index_to_char freq

for ii=1:no_of_chars
    char_to_index(ii)=ii+1;
    index_to_char(ii+1)=ii;
end

for ii=1:no_of_symbols
    freq(ii)=1;
    cum_freq(ii)=no_of_symbols-ii;
end

freq(1)=0;

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