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Reduced row echelon form: Difference between revisions

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Reduced row echelon form (view source)

Revision as of 02:51, 6 June 2021

7,338 bytes added ,  3 years ago
m
→‎{{header|Phix}}: added syntax colouring the hard way
m (→‎{{header|Phix}}: added syntax colouring the hard way)
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=={{header|Phix}}==
{{Trans|Euphoria}}
<!--<lang Phix>function ToReducedRowEchelonForm(sequence Mphixonline)-->
<span style="color: #008080;">with</span> <span style="color: #008080;">javascript_semantics</span>
integer lead = 1,
<span style="color: #008080;">function</span> <span style="color: #000000;">ToReducedRowEchelonForm</span><span style="color: #0000FF;">(</span><span style="color: #004080;">sequence</span> <span style="color: #000000;">M</span><span style="color: #0000FF;">)</span>
rowCount = length(M),
<span style="color: #004080;">integer</span> <span style="color: #000000;">lead</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">1</span><span style="color: #0000FF;">,</span>
columnCount = length(M[1]),
<span style="color: #000000;">rowCount</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">M</span><span style="color: #0000FF;">),</span>
i
<span style="color: #000000;">columnCount</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">M</span><span style="color: #0000FF;">[</span><span style="color: #000000;">1</span><span style="color: #0000FF;">]),</span>
for r=1 to rowCount do
if lead><span style=columnCount"color: then exit end if#000000;">i</span>
<span style="color: #008080;">for</span> <span style="color: #000000;">r</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">rowCount</span> <span style="color: #008080;">do</span>
i = r
<span style="color: #008080;">if</span> <span style="color: #000000;">lead</span><span style="color: #0000FF;">>=</span><span style="color: #000000;">columnCount</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>
while M[i][lead]=0 do
<span style="color: #000000;">i</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">r</span>
i += 1
<span style="color: #008080;">while</span> <span style="color: #000000;">M</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">][</span><span style="color: #000000;">lead</span><span style="color: #0000FF;">]=</span><span style="color: #000000;">0</span> <span style="color: #008080;">do</span>
if i=rowCount then
<span style="color: #000000;">i</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">1</span>
i = r
<span style="color: #008080;">if</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">rowCount</span> <span style="color: #008080;">then</span>
lead += 1
<span style="color: #000000;">i</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">r</span>
if lead=columnCount then exit end if
<span style="color: #000000;">lead</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">1</span>
end if
<span style="color: #008080;">if</span> <span style="color: #000000;">lead</span><span style="color: #0000FF;">=</span><span style="color: #000000;">columnCount</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>
end while
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
-- nb M[i] is assigned before M[r], which matters when i=r:
<span style="color: #008080;">end</span> <span style="color: #008080;">while</span>
{M[r],M[i]} = {sq_div(M[i],M[i][lead]),M[r]}
<span style="color: #004080;">object</span> <span style="color: #000000;">mr</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">sq_div</span><span style="color: #0000FF;">(</span><span style="color: #000000;">M</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">],</span><span style="color: #000000;">M</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">][</span><span style="color: #000000;">lead</span><span style="color: #0000FF;">])</span>
for j=1 to rowCount do
<span style="color: #000000;">M</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;">M</span><span style="color: #0000FF;">[</span><span style="color: #000000;">r</span><span style="color: #0000FF;">]</span>
if j!=r then
<span style="color: #000000;">M</span><span style="color: #0000FF;">[</span><span style="color: #000000;">r</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">mr</span>
M[j] = sq_sub(M[j],sq_mul(M[j][lead],M[r]))
<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: #000000;">rowCount</span> <span style="color: #008080;">do</span>
end if
<span style="color: #008080;">if</span> <span style="color: #000000;">j</span><span style="color: #0000FF;">!=</span><span style="color: #000000;">r</span> <span style="color: #008080;">then</span>
end for
<span style="color: #000000;">M</span><span style="color: #0000FF;">[</span><span style="color: #000000;">j</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">sq_sub</span><span style="color: #0000FF;">(</span><span style="color: #000000;">M</span><span style="color: #0000FF;">[</span><span style="color: #000000;">j</span><span style="color: #0000FF;">],</span><span style="color: #7060A8;">sq_mul</span><span style="color: #0000FF;">(</span><span style="color: #000000;">M</span><span style="color: #0000FF;">[</span><span style="color: #000000;">j</span><span style="color: #0000FF;">][</span><span style="color: #000000;">lead</span><span style="color: #0000FF;">],</span><span style="color: #000000;">M</span><span style="color: #0000FF;">[</span><span style="color: #000000;">r</span><span style="color: #0000FF;">]))</span>
lead += 1
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
end for
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
return M
<span style="color: #000000;">lead</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">1</span>
end function
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
<span style="color: #008080;">return</span> <span style="color: #000000;">M</span>
? ToReducedRowEchelonForm(
<span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
{ { 1, 2, -1, -4 },
{ 2, 3, -1, -11 },
<span style="color: #0000FF;">?</span> <span style="color: #000000;">ToReducedRowEchelonForm</span><span style="color: #0000FF;">(</span>
{ -2, 0, -3, 22 } })</lang>
<span style="color: #0000FF;">{</span> <span style="color: #0000FF;">{</span> <span style="color: #000000;">1</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">2</span><span style="color: #0000FF;">,</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;">4</span> <span style="color: #0000FF;">},</span>
<span style="color: #0000FF;">{</span> <span style="color: #000000;">2</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">3</span><span style="color: #0000FF;">,</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;">11</span> <span style="color: #0000FF;">},</span>
<span style="color: #0000FF;">{</span> <span style="color: #0000FF;">-</span><span style="color: #000000;">2</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">0</span><span style="color: #0000FF;">,</span> <span style="color: #0000FF;">-</span><span style="color: #000000;">3</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">22</span> <span style="color: #0000FF;">}</span> <span style="color: #0000FF;">})</span>
<!--</lang>-->
{{out}}
<pre>
Petelomax
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