Arithmetic coding/As a generalized change of radix: Difference between revisions
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m (→{{header|Phix}}: added syntax colouring the hard way, mpz_get_si() => mpz_get_integer().) |
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{{trans|Kotlin}} |
{{trans|Kotlin}} |
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{{libheader|Phix/mpfr}} |
{{libheader|Phix/mpfr}} |
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<lang Phix> |
<!--<lang Phix>(phixonline)--> |
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<span style="color: #008080;">with</span> <span style="color: #008080;">javascript_semantics</span> |
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<span style="color: #008080;">include</span> <span style="color: #004080;">mpfr</span><span style="color: #0000FF;">.</span><span style="color: #000000;">e</span> |
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function cumulative_freq(sequence freq) |
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integer total = 0, |
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<span style="color: #008080;">function</span> <span style="color: #000000;">cumulative_freq</span><span style="color: #0000FF;">(</span><span style="color: #004080;">sequence</span> <span style="color: #000000;">freq</span><span style="color: #0000FF;">)</span> |
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l = length(freq) |
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<span style="color: #004080;">integer</span> <span style="color: #000000;">total</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span><span style="color: #0000FF;">,</span> |
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sequence cf = repeat(-1,l) |
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<span style="color: #000000;">l</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">freq</span><span style="color: #0000FF;">)</span> |
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for c=1 to l do |
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<span style="color: #004080;">sequence</span> <span style="color: #000000;">cf</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">l</span><span style="color: #0000FF;">)</span> |
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integer v = freq[c] |
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<span style="color: #008080;">for</span> <span style="color: #000000;">c</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">l</span> <span style="color: #008080;">do</span> |
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if v!=0 then |
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<span style="color: #004080;">integer</span> <span style="color: #000000;">v</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">freq</span><span style="color: #0000FF;">[</span><span style="color: #000000;">c</span><span style="color: #0000FF;">]</span> |
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cf[c] = total |
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<span style="color: #008080;">if</span> <span style="color: #000000;">v</span><span style="color: #0000FF;">!=</span><span style="color: #000000;">0</span> <span style="color: #008080;">then</span> |
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total += v |
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<span style="color: #000000;">cf</span><span style="color: #0000FF;">[</span><span style="color: #000000;">c</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">total</span> |
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end if |
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<span style="color: #000000;">total</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">v</span> |
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end for |
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<span style="color: #008080;">end</span> <span style="color: #008080;">if</span> |
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return cf |
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<span style="color: #008080;">end</span> <span style="color: #008080;">for</span> |
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end function |
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<span style="color: #008080;">return</span> <span style="color: #000000;">cf</span> |
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<span style="color: #008080;">end</span> <span style="color: #008080;">function</span> |
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function arithmethic_coding(string str, integer radix) |
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sequence freq = repeat(0,256) |
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<span style="color: #008080;">function</span> <span style="color: #000000;">arithmethic_coding</span><span style="color: #0000FF;">(</span><span style="color: #004080;">string</span> <span style="color: #000000;">str</span><span style="color: #0000FF;">,</span> <span style="color: #004080;">integer</span> <span style="color: #000000;">radix</span><span style="color: #0000FF;">)</span> |
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for i=1 to length(str) do |
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<span style="color: #004080;">sequence</span> <span style="color: #000000;">freq</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">256</span><span style="color: #0000FF;">)</span> |
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freq[str[i]+1] += 1 |
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<span style="color: #008080;">for</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">str</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">do</span> |
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end for |
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<span style="color: #000000;">freq</span><span style="color: #0000FF;">[</span><span style="color: #000000;">str</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]+</span><span style="color: #000000;">1</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">1</span> |
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sequence cf = cumulative_freq(freq) |
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<span style="color: #008080;">end</span> <span style="color: #008080;">for</span> |
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integer base = length(str) |
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<span style="color: #004080;">sequence</span> <span style="color: #000000;">cf</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">cumulative_freq</span><span style="color: #0000FF;">(</span><span style="color: #000000;">freq</span><span style="color: #0000FF;">)</span> |
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mpz lo = mpz_init(0), -- lower bound |
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<span style="color: #004080;">integer</span> <span style="color: #000000;">base</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">str</span><span style="color: #0000FF;">)</span> |
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pf = mpz_init(1), -- product of all frequencies |
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<span style="color: #004080;">mpz</span> <span style="color: #000000;">lo</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">mpz_init</span><span style="color: #0000FF;">(</span><span style="color: #000000;">0</span><span style="color: #0000FF;">),</span> <span style="color: #000080;font-style:italic;">-- lower bound</span> |
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t1 = mpz_init(), -- temp |
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<span style="color: #000000;">pf</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">mpz_init</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">),</span> <span style="color: #000080;font-style:italic;">-- product of all frequencies</span> |
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t2 = mpz_init(), -- temp |
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<span style="color: #000000;">t1</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">mpz_init</span><span style="color: #0000FF;">(),</span> <span style="color: #000080;font-style:italic;">-- temp</span> |
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hi = mpz_init(), -- upper bound |
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<span style="color: #000000;">t2</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">mpz_init</span><span style="color: #0000FF;">(),</span> <span style="color: #000080;font-style:italic;">-- temp</span> |
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diff = mpz_init() |
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<span style="color: #000000;">hi</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">mpz_init</span><span style="color: #0000FF;">(),</span> <span style="color: #000080;font-style:italic;">-- upper bound</span> |
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-- Each term is multiplied by the product of the |
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<span style="color: #000000;">diff</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">mpz_init</span><span style="color: #0000FF;">()</span> |
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-- frequencies of all previously occurring symbols |
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<span style="color: #000080;font-style:italic;">-- Each term is multiplied by the product of the |
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for i=1 to length(str) do |
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-- frequencies of all previously occurring symbols</span> |
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integer c = str[i]+1 |
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<span style="color: #008080;">for</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">str</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">do</span> |
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integer x = cf[c] |
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<span style="color: #004080;">integer</span> <span style="color: #000000;">c</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">str</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]+</span><span style="color: #000000;">1</span> |
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mpz_mul_si(t1,lo,base) |
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<span style="color: #004080;">integer</span> <span style="color: #000000;">x</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">cf</span><span style="color: #0000FF;">[</span><span style="color: #000000;">c</span><span style="color: #0000FF;">]</span> |
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mpz_mul_si(t2,pf,x) |
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<span style="color: #7060A8;">mpz_mul_si</span><span style="color: #0000FF;">(</span><span style="color: #000000;">t1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">lo</span><span style="color: #0000FF;">,</span><span style="color: #000000;">base</span><span style="color: #0000FF;">)</span> |
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mpz_add(lo,t1,t2) |
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<span style="color: #7060A8;">mpz_mul_si</span><span style="color: #0000FF;">(</span><span style="color: #000000;">t2</span><span style="color: #0000FF;">,</span><span style="color: #000000;">pf</span><span style="color: #0000FF;">,</span><span style="color: #000000;">x</span><span style="color: #0000FF;">)</span> |
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mpz_mul_si(pf,pf,freq[c]) |
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<span style="color: #7060A8;">mpz_add</span><span style="color: #0000FF;">(</span><span style="color: #000000;">lo</span><span style="color: #0000FF;">,</span><span style="color: #000000;">t1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">t2</span><span style="color: #0000FF;">)</span> |
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end for |
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<span style="color: #7060A8;">mpz_mul_si</span><span style="color: #0000FF;">(</span><span style="color: #000000;">pf</span><span style="color: #0000FF;">,</span><span style="color: #000000;">pf</span><span style="color: #0000FF;">,</span><span style="color: #000000;">freq</span><span style="color: #0000FF;">[</span><span style="color: #000000;">c</span><span style="color: #0000FF;">])</span> |
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mpz_add(hi,lo,pf) |
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<span style="color: #008080;">end</span> <span style="color: #008080;">for</span> |
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integer powr = 0 |
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<span style="color: #7060A8;">mpz_add</span><span style="color: #0000FF;">(</span><span style="color: #000000;">hi</span><span style="color: #0000FF;">,</span><span style="color: #000000;">lo</span><span style="color: #0000FF;">,</span><span style="color: #000000;">pf</span><span style="color: #0000FF;">)</span> |
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while true do |
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<span style="color: #004080;">integer</span> <span style="color: #000000;">powr</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span> |
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{} = mpz_fdiv_q_ui(pf,pf,radix) |
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<span style="color: #008080;">while</span> <span style="color: #004600;">true</span> <span style="color: #008080;">do</span> |
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if mpz_cmp_si(pf,0)=0 then exit end if |
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<span style="color: #0000FF;">{}</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">mpz_fdiv_q_ui</span><span style="color: #0000FF;">(</span><span style="color: #000000;">pf</span><span style="color: #0000FF;">,</span><span style="color: #000000;">pf</span><span style="color: #0000FF;">,</span><span style="color: #000000;">radix</span><span style="color: #0000FF;">)</span> |
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powr += 1 |
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<span style="color: #008080;">if</span> <span style="color: #7060A8;">mpz_cmp_si</span><span style="color: #0000FF;">(</span><span style="color: #000000;">pf</span><span style="color: #0000FF;">,</span><span style="color: #000000;">0</span><span style="color: #0000FF;">)=</span><span style="color: #000000;">0</span> <span style="color: #008080;">then</span> <span style="color: #008080;">exit</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span> |
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end while |
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<span style="color: #000000;">powr</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">1</span> |
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mpz_sub_ui(hi,hi,1) |
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<span style="color: #008080;">end</span> <span style="color: #008080;">while</span> |
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mpz_ui_pow_ui(t1,radix,powr) |
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<span style="color: #7060A8;">mpz_sub_ui</span><span style="color: #0000FF;">(</span><span style="color: #000000;">hi</span><span style="color: #0000FF;">,</span><span style="color: #000000;">hi</span><span style="color: #0000FF;">,</span><span style="color: #000000;">1</span><span style="color: #0000FF;">)</span> |
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mpz_fdiv_q(diff,hi,t1) |
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<span style="color: #7060A8;">mpz_ui_pow_ui</span><span style="color: #0000FF;">(</span><span style="color: #000000;">t1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">radix</span><span style="color: #0000FF;">,</span><span style="color: #000000;">powr</span><span style="color: #0000FF;">)</span> |
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return {diff, powr, freq} |
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<span style="color: #7060A8;">mpz_fdiv_q</span><span style="color: #0000FF;">(</span><span style="color: #000000;">diff</span><span style="color: #0000FF;">,</span><span style="color: #000000;">hi</span><span style="color: #0000FF;">,</span><span style="color: #000000;">t1</span><span style="color: #0000FF;">)</span> |
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end function |
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<span style="color: #008080;">return</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">diff</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">powr</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">freq</span><span style="color: #0000FF;">}</span> |
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<span style="color: #008080;">end</span> <span style="color: #008080;">function</span> |
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function arithmethic_decoding(mpz num, integer radix, pwr, sequence freq) |
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mpz enc = mpz_init(), |
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<span style="color: #008080;">function</span> <span style="color: #000000;">arithmethic_decoding</span><span style="color: #0000FF;">(</span><span style="color: #004080;">mpz</span> <span style="color: #000000;">num</span><span style="color: #0000FF;">,</span> <span style="color: #004080;">integer</span> <span style="color: #000000;">radix</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">pwr</span><span style="color: #0000FF;">,</span> <span style="color: #004080;">sequence</span> <span style="color: #000000;">freq</span><span style="color: #0000FF;">)</span> |
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pow = mpz_init(), |
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<span style="color: #004080;">mpz</span> <span style="color: #000000;">enc</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">mpz_init</span><span style="color: #0000FF;">(),</span> |
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tmp = mpz_init() |
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<span style="color: #000000;">pow</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">mpz_init</span><span style="color: #0000FF;">(),</span> |
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mpz_ui_pow_ui(enc,radix,pwr) |
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<span style="color: #000000;">tmp</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">mpz_init</span><span style="color: #0000FF;">()</span> |
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mpz_mul(enc,num,enc) |
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<span style="color: #7060A8;">mpz_ui_pow_ui</span><span style="color: #0000FF;">(</span><span style="color: #000000;">enc</span><span style="color: #0000FF;">,</span><span style="color: #000000;">radix</span><span style="color: #0000FF;">,</span><span style="color: #000000;">pwr</span><span style="color: #0000FF;">)</span> |
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integer base = sum(freq) |
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<span style="color: #7060A8;">mpz_mul</span><span style="color: #0000FF;">(</span><span style="color: #000000;">enc</span><span style="color: #0000FF;">,</span><span style="color: #000000;">num</span><span style="color: #0000FF;">,</span><span style="color: #000000;">enc</span><span style="color: #0000FF;">)</span> |
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sequence cf = cumulative_freq(freq) |
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<span style="color: #004080;">integer</span> <span style="color: #000000;">base</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">sum</span><span style="color: #0000FF;">(</span><span style="color: #000000;">freq</span><span style="color: #0000FF;">)</span> |
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sequence dict = repeat(0,base+1) |
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<span style="color: #004080;">sequence</span> <span style="color: #000000;">cf</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">cumulative_freq</span><span style="color: #0000FF;">(</span><span style="color: #000000;">freq</span><span style="color: #0000FF;">)</span> |
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for i=1 to length(cf) do |
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<span style="color: #004080;">sequence</span> <span style="color: #000000;">dict</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">base</span><span style="color: #0000FF;">+</span><span style="color: #000000;">1</span><span style="color: #0000FF;">)</span> |
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integer v = cf[i] |
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<span style="color: #008080;">for</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">cf</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">do</span> |
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if v!=-1 then dict[v+1] = i-1 end if |
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<span style="color: #004080;">integer</span> <span style="color: #000000;">v</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">cf</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]</span> |
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end for |
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<span style="color: #008080;">if</span> <span style="color: #000000;">v</span><span style="color: #0000FF;">!=-</span><span style="color: #000000;">1</span> <span style="color: #008080;">then</span> <span style="color: #000000;">dict</span><span style="color: #0000FF;">[</span><span style="color: #000000;">v</span><span style="color: #0000FF;">+</span><span style="color: #000000;">1</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span> |
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-- Fill the gaps in the dictionary |
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<span style="color: #008080;">end</span> <span style="color: #008080;">for</span> |
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integer lchar = -1 |
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<span style="color: #000080;font-style:italic;">-- Fill the gaps in the dictionary</span> |
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for i=0 to base do |
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<span style="color: #004080;">integer</span> <span style="color: #000000;">lchar</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">-</span><span style="color: #000000;">1</span> |
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integer v = dict[i+1] |
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<span style="color: #008080;">for</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">0</span> <span style="color: #008080;">to</span> <span style="color: #000000;">base</span> <span style="color: #008080;">do</span> |
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if v!=0 then |
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<span style="color: #004080;">integer</span> <span style="color: #000000;">v</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">dict</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">+</span><span style="color: #000000;">1</span><span style="color: #0000FF;">]</span> |
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lchar = v |
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<span style="color: #008080;">if</span> <span style="color: #000000;">v</span><span style="color: #0000FF;">!=</span><span style="color: #000000;">0</span> <span style="color: #008080;">then</span> |
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elsif lchar!=-1 then |
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<span style="color: #000000;">lchar</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">v</span> |
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dict[i+1] = lchar |
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<span style="color: #008080;">elsif</span> <span style="color: #000000;">lchar</span><span style="color: #0000FF;">!=-</span><span style="color: #000000;">1</span> <span style="color: #008080;">then</span> |
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end if |
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<span style="color: #000000;">dict</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">+</span><span style="color: #000000;">1</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">lchar</span> |
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end for |
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<span style="color: #008080;">end</span> <span style="color: #008080;">if</span> |
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-- Decode the input number |
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<span style="color: #008080;">end</span> <span style="color: #008080;">for</span> |
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string decoded = "" |
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<span style="color: #000080;font-style:italic;">-- Decode the input number</span> |
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for i=base-1 to 0 by -1 do |
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<span style="color: #004080;">string</span> <span style="color: #000000;">decoded</span> <span style="color: #0000FF;">=</span> <span style="color: #008000;">""</span> |
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mpz_ui_pow_ui(pow,base,i) |
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<span style="color: #008080;">for</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">base</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">0</span> <span style="color: #008080;">by</span> <span style="color: #0000FF;">-</span><span style="color: #000000;">1</span> <span style="color: #008080;">do</span> |
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mpz_fdiv_q(tmp,enc,pow) |
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<span style="color: #7060A8;">mpz_ui_pow_ui</span><span style="color: #0000FF;">(</span><span style="color: #000000;">pow</span><span style="color: #0000FF;">,</span><span style="color: #000000;">base</span><span style="color: #0000FF;">,</span><span style="color: #000000;">i</span><span style="color: #0000FF;">)</span> |
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integer div = mpz_get_si(tmp), |
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<span style="color: #7060A8;">mpz_fdiv_q</span><span style="color: #0000FF;">(</span><span style="color: #000000;">tmp</span><span style="color: #0000FF;">,</span><span style="color: #000000;">enc</span><span style="color: #0000FF;">,</span><span style="color: #000000;">pow</span><span style="color: #0000FF;">)</span> |
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c = dict[div+1], |
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<span style="color: #004080;">integer</span> <span style="color: #000000;">div</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">mpz_get_integer</span><span style="color: #0000FF;">(</span><span style="color: #000000;">tmp</span><span style="color: #0000FF;">),</span> |
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fv = freq[c+1], |
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<span style="color: #000000;">c</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">dict</span><span style="color: #0000FF;">[</span><span style="color: #000000;">div</span><span style="color: #0000FF;">+</span><span style="color: #000000;">1</span><span style="color: #0000FF;">],</span> |
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cv = cf[c+1] |
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<span style="color: #000000;">fv</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">freq</span><span style="color: #0000FF;">[</span><span style="color: #000000;">c</span><span style="color: #0000FF;">+</span><span style="color: #000000;">1</span><span style="color: #0000FF;">],</span> |
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mpz_mul_si(tmp,pow,cv) |
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<span style="color: #000000;">cv</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">cf</span><span style="color: #0000FF;">[</span><span style="color: #000000;">c</span><span style="color: #0000FF;">+</span><span style="color: #000000;">1</span><span style="color: #0000FF;">]</span> |
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mpz_sub(tmp,enc,tmp) |
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<span style="color: #7060A8;">mpz_mul_si</span><span style="color: #0000FF;">(</span><span style="color: #000000;">tmp</span><span style="color: #0000FF;">,</span><span style="color: #000000;">pow</span><span style="color: #0000FF;">,</span><span style="color: #000000;">cv</span><span style="color: #0000FF;">)</span> |
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{} = mpz_fdiv_q_ui(enc,tmp,fv) |
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<span style="color: #7060A8;">mpz_sub</span><span style="color: #0000FF;">(</span><span style="color: #000000;">tmp</span><span style="color: #0000FF;">,</span><span style="color: #000000;">enc</span><span style="color: #0000FF;">,</span><span style="color: #000000;">tmp</span><span style="color: #0000FF;">)</span> |
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decoded &= c |
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<span style="color: #0000FF;">{}</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">mpz_fdiv_q_ui</span><span style="color: #0000FF;">(</span><span style="color: #000000;">enc</span><span style="color: #0000FF;">,</span><span style="color: #000000;">tmp</span><span style="color: #0000FF;">,</span><span style="color: #000000;">fv</span><span style="color: #0000FF;">)</span> |
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end for |
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<span style="color: #000000;">decoded</span> <span style="color: #0000FF;">&=</span> <span style="color: #000000;">c</span> |
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return decoded |
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<span style="color: #008080;">end</span> <span style="color: #008080;">for</span> |
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end function |
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<span style="color: #008080;">return</span> <span style="color: #000000;">decoded</span> |
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<span style="color: #008080;">end</span> <span style="color: #008080;">function</span> |
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constant tests = {"DABDDB", "DABDDBBDDBA", "ABRACADABRA", "TOBEORNOTTOBEORTOBEORNOT"}, |
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radix = 10 |
|||
<span style="color: #008080;">constant</span> <span style="color: #000000;">tests</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{</span><span style="color: #008000;">"DABDDB"</span><span style="color: #0000FF;">,</span> <span style="color: #008000;">"DABDDBBDDBA"</span><span style="color: #0000FF;">,</span> <span style="color: #008000;">"ABRACADABRA"</span><span style="color: #0000FF;">,</span> <span style="color: #008000;">"TOBEORNOTTOBEORTOBEORNOT"</span><span style="color: #0000FF;">},</span> |
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<span style="color: #000000;">radix</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">10</span> |
|||
for i=1 to length(tests) do |
|||
string str = tests[i] |
|||
<span style="color: #008080;">for</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">tests</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">do</span> |
|||
{mpz enc, integer pow, sequence freq} = arithmethic_coding(str, radix) |
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<span style="color: #004080;">string</span> <span style="color: #000000;">str</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">tests</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]</span> |
|||
string dec = arithmethic_decoding(enc, radix, pow, freq), |
|||
<span style="color: #0000FF;">{</span><span style="color: #004080;">mpz</span> <span style="color: #000000;">enc</span><span style="color: #0000FF;">,</span> <span style="color: #004080;">integer</span> <span style="color: #000000;">pow</span><span style="color: #0000FF;">,</span> <span style="color: #004080;">sequence</span> <span style="color: #000000;">freq</span><span style="color: #0000FF;">}</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">arithmethic_coding</span><span style="color: #0000FF;">(</span><span style="color: #000000;">str</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">radix</span><span style="color: #0000FF;">)</span> |
|||
ok = iff(str=dec?"(ok)":"***ERROR***"), |
|||
<span style="color: #004080;">string</span> <span style="color: #000000;">dec</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">arithmethic_decoding</span><span style="color: #0000FF;">(</span><span style="color: #000000;">enc</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">radix</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">pow</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">freq</span><span style="color: #0000FF;">),</span> |
|||
encs = mpz_get_str(enc) |
|||
<span style="color: #000000;">ok</span> <span style="color: #0000FF;">=</span> <span style="color: #008080;">iff</span><span style="color: #0000FF;">(</span><span style="color: #000000;">str</span><span style="color: #0000FF;">=</span><span style="color: #000000;">dec</span><span style="color: #0000FF;">?</span><span style="color: #008000;">"(ok)"</span><span style="color: #0000FF;">:</span><span style="color: #008000;">"***ERROR***"</span><span style="color: #0000FF;">),</span> |
|||
printf(1,"%-25s=> %19s * %d^%d %s\n",{str, encs, radix, pow, ok}) |
|||
<span style="color: #000000;">encs</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">mpz_get_str</span><span style="color: #0000FF;">(</span><span style="color: #000000;">enc</span><span style="color: #0000FF;">)</span> |
|||
end for</lang> |
|||
<span style="color: #7060A8;">printf</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"%-25s=> %19s * %d^%d %s\n"</span><span style="color: #0000FF;">,{</span><span style="color: #000000;">str</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">encs</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">radix</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">pow</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">ok</span><span style="color: #0000FF;">})</span> |
|||
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span> |
|||
<!--</lang>--> |
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{{out}} |
{{out}} |
||
<pre> |
<pre> |