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Apply a digital filter (direct form II transposed): Difference between revisions

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Apply a digital filter (direct form II transposed) (view source)

Revision as of 16:24, 29 December 2021

7,553 bytes added ,  2 years ago
m
→‎{{header|Phix}}: added syntax colouring, fixed a couple of bugs
(→‎{{header|Haskell}}: minor details)
m (→‎{{header|Phix}}: added syntax colouring, fixed a couple of bugs)
Line 1,119:
Note however that the a[j]* starts from index 2, unlike Julia/C/Raku/Rust/Sidef/zkl,
but the same as C++/C#/D/Java/Kotlin - and it does not seem to make any difference...
<!--<lang Phix>(phixonline)-->
<lang Phix>function direct_form_II_transposed_filter(sequence a, b, signal)
<span style="color: #008080;">with</span> <span style="color: #008080;">javascript_semantics</span>
sequence result = repeat(0,length(signal))
<span style="color: #008080;">function</span> <span style="color: #000000;">direct_form_II_transposed_filter</span><span style="color: #0000FF;">(</span><span style="color: #004080;">sequence</span> <span style="color: #000000;">a</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">b</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">signal</span><span style="color: #0000FF;">)</span>
for i=1 to length(in) do
<span style="color: #004080;">sequence</span> <span style="color: #000000;">result</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: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">signal</span><span style="color: #0000FF;">))</span>
atom tmp = 0
<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;">signal</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">do</span>
for j=1 to min(i,length(b)) do tmp += b[j]*signal[i-j+1] end for
<span style="color: #004080;">atom</span> <span style="color: #000000;">tmp</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span>
for j=2 to min(i,length(a)) do tmp -= a[j]*result[i-j+1] end for
<span style="color: #008080;">for</span> <span style="color: #000000;">j</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #7060A8;">min</span><span style="color: #0000FF;">(</span><span style="color: #000000;">i</span><span style="color: #0000FF;">,</span><span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">b</span><span style="color: #0000FF;">))</span> <span style="color: #008080;">do</span> <span style="color: #000000;">tmp</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">b</span><span style="color: #0000FF;">[</span><span style="color: #000000;">j</span><span style="color: #0000FF;">]*</span><span style="color: #000000;">signal</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">-</span><span style="color: #000000;">j</span><span style="color: #0000FF;">+</span><span style="color: #000000;">1</span><span style="color: #0000FF;">]</span> <span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
result[i] = tmp/a[1]
<span style="color: #008080;">for</span> <span style="color: #000000;">j</span><span style="color: #0000FF;">=</span><span style="color: #000000;">2</span> <span style="color: #008080;">to</span> <span style="color: #7060A8;">min</span><span style="color: #0000FF;">(</span><span style="color: #000000;">i</span><span style="color: #0000FF;">,</span><span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">a</span><span style="color: #0000FF;">))</span> <span style="color: #008080;">do</span> <span style="color: #000000;">tmp</span> <span style="color: #0000FF;">-=</span> <span style="color: #000000;">a</span><span style="color: #0000FF;">[</span><span style="color: #000000;">j</span><span style="color: #0000FF;">]*</span><span style="color: #000000;">result</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">-</span><span style="color: #000000;">j</span><span style="color: #0000FF;">+</span><span style="color: #000000;">1</span><span style="color: #0000FF;">]</span> <span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
end for
<span style="color: #000000;">result</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">tmp</span><span style="color: #0000FF;">/</span><span style="color: #000000;">a</span><span style="color: #0000FF;">[</span><span style="color: #000000;">1</span><span style="color: #0000FF;">]</span>
return result
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
end function
<span style="color: #008080;">return</span> <span style="color: #000000;">result</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
constant acoef = {1.00000000, -2.77555756e-16, 3.33333333e-01, -1.85037171e-17},
bcoef = {0.16666667, 0.5, 0.5, 0.16666667}
<span style="color: #008080;">constant</span> <span style="color: #000000;">acoef</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">1.00000000</span><span style="color: #0000FF;">,</span> <span style="color: #0000FF;">-</span><span style="color: #000000;">2.77555756e-16</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">3.33333333e-01</span><span style="color: #0000FF;">,</span> <span style="color: #0000FF;">-</span><span style="color: #000000;">1.85037171e-17</span><span style="color: #0000FF;">},</span>
signal = {-0.917843918645,0.141984778794,1.20536903482,0.190286794412,-0.662370894973,
<span style="color: #000000;">bcoef</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">0.16666667</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">0.5</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">0.5</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">0.16666667</span><span style="color: #0000FF;">},</span>
-1.00700480494,-0.404707073677,0.800482325044,0.743500089861,1.01090520172,
<span style="color: #000000;">signal</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{-</span><span style="color: #000000;">0.917843918645</span><span style="color: #0000FF;">,</span><span style="color: #000000;">0.141984778794</span><span style="color: #0000FF;">,</span><span style="color: #000000;">1.20536903482</span><span style="color: #0000FF;">,</span><span style="color: #000000;">0.190286794412</span><span style="color: #0000FF;">,-</span><span style="color: #000000;">0.662370894973</span><span style="color: #0000FF;">,</span>
0.741527555207,0.277841675195,0.400833448236,-0.2085993586,-0.172842103641,
<span style="color: #0000FF;">-</span><span style="color: #000000;">1.00700480494</span><span style="color: #0000FF;">,-</span><span style="color: #000000;">0.404707073677</span><span style="color: #0000FF;">,</span><span style="color: #000000;">0.800482325044</span><span style="color: #0000FF;">,</span><span style="color: #000000;">0.743500089861</span><span style="color: #0000FF;">,</span><span style="color: #000000;">1.01090520172</span><span style="color: #0000FF;">,</span>
-0.134316096293,0.0259303398477,0.490105989562,0.549391221511,0.9047198589},
<span style="color: #000000;">0.741527555207</span><span style="color: #0000FF;">,</span><span style="color: #000000;">0.277841675195</span><span style="color: #0000FF;">,</span><span style="color: #000000;">0.400833448236</span><span style="color: #0000FF;">,-</span><span style="color: #000000;">0.2085993586</span><span style="color: #0000FF;">,-</span><span style="color: #000000;">0.172842103641</span><span style="color: #0000FF;">,</span>
 
<span style="color: #0000FF;">-</span><span style="color: #000000;">0.134316096293</span><span style="color: #0000FF;">,</span><span style="color: #000000;">0.0259303398477</span><span style="color: #0000FF;">,</span><span style="color: #000000;">0.490105989562</span><span style="color: #0000FF;">,</span><span style="color: #000000;">0.549391221511</span><span style="color: #0000FF;">,</span><span style="color: #000000;">0.9047198589</span><span style="color: #0000FF;">}</span>
pp(direct_form_II_transposed_filter(acoef, bcoef, signal),{pp_FltFmt,"%9.6f",pp_Maxlen,110})</lang>
<span style="color: #7060A8;">pp</span><span style="color: #0000FF;">(</span><span style="color: #000000;">direct_form_II_transposed_filter</span><span style="color: #0000FF;">(</span><span style="color: #000000;">acoef</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">bcoef</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">signal</span><span style="color: #0000FF;">),{</span><span style="color: #004600;">pp_FltFmt</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"%9.6f"</span><span style="color: #0000FF;">,</span><span style="color: #004600;">pp_Maxlen</span><span style="color: #0000FF;">,</span><span style="color: #000000;">110</span><span style="color: #0000FF;">})</span>
<!--</lang>-->
{{out}}
<pre>
Petelomax
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