Programmer Guide/Command Reference/EVAL/pgitest: Difference between revisions

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:<code>pgitest(<var>X</var>, <var>IX</var>, <var>PX<sub>scalar</sub></var>, <var>PY<sub>scalar</sub></var>)</code>
:<code>pgitest(<var>X</var>, <var>IX</var>, <var>PX<sub>scalar</sub></var>, <var>PY<sub>scalar</sub></var>)</code>
:;<var>X</var>:a [[../#polygons|closed point-list]] or a [[../#polygons|polygon-stream]] defining one or more polygons.
:;<var>X</var>:a [[../#polygons|closed point-list]] or a [[../#polygons|polygon-stream]] defining one or more polygons.
:;<var>IX</var>:The index of the polygon of ''X'' to be tested; 0 <= <var>IX</var> < ''N'' (= <code>[[../pgget|pgget]](''X'')</code>)
:;<var>IX</var>:The index of the polygon of ''X'' to be tested; 0 <= <var>IX</var> < <code>[[../pgget|pgget]](''X'')</code>)
:;<var>PX, PY</var>: The point ''P''=<''PX'',''PY''> to be tested.
:;<var>PX, PY</var>: The point ''P''=<''PX'',''PY''> to be tested.
;Result 1: The result ''r'' is a scaler.
;Result 1: The result ''r'' is a scaler.

Revision as of 07:49, 20 April 2011

Check the relation (outside, inside, overlap) of a given point, line or simple polygon p to the polygon x.


Usage 1
pgitest(X, IX, PXscalar, PYscalar)
X
a closed point-list or a polygon-stream defining one or more polygons.
IX
The index of the polygon of X to be tested; 0 <= IX < pgget(X))
PX, PY
The point P=<PX,PY> to be tested.
Result 1
The result r is a scaler.
r=0 ... point P is outside the polygon
r=1 ... point P is inside the polygon
pgitest(X, I, PXscalar, PYvector)
pgitest(X, I, PXvector, PYscalar)
pgitest(X, I, PXvector, PYvector)


X
A closed point-list or a polygon-stream defining one or more polygons.
Result 1
The number of simple polygons N stored in X. If the result is 0, X contains no valid polygons.

Usage 2
pgget(X, I, fmt)
X
A closed point-list or a polygon-stream defining one or more polygons.
I
The index of the polygon to be returned; 0 <= I < N (= pgget(X))
fmt
The format of the result.:
fmt=0 ... return the I-th polygon of X as polygon-stream
fmt=1 ... return the polygon-stream header (a 8x2 matrix) of the I-th polygon of X
Result 2
The I-th polygon stored in X in the format selected by fmt.

See also
pginit, pgitest, pgiline, pgxgrid, pgsplit, pgtrans, pghull


<function list>

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