Shoelace formula for polygonal area: Difference between revisions
Shoelace formula for polygonal area (view source)
Revision as of 21:43, 14 December 2020
, 3 years agoAdded XPL0 example.
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(Added XPL0 example.) |
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<pre>
The polygon with vertices at [[3, 4], [5, 11], [12, 8], [9, 5], [5, 6]] has an area of 30.
</pre>
=={{header|XPL0}}==
<lang XPL0>proc real Shoelace(N, X, Y);
int N, X, Y;
int S, I;
[S:= 0;
for I:= 0 to N-2 do
S:= S + X(I)*Y(I+1) - X(I+1)*Y(I);
S:= S + X(I)*Y(0) - X(0)*Y(I);
return float(abs(S)) / 2.0;
];
RlOut(0, Shoelace(5, [3, 5, 12, 9, 5], [4, 11, 8, 5, 6]))</lang>
{{out}}
<pre>
30.00000
</pre>
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