moments_any_points_xldmoments_any_points_xldMomentsAnyPointsXldMomentsAnyPointsXldmoments_any_points_xld (算子)

名称

moments_any_points_xldmoments_any_points_xldMomentsAnyPointsXldMomentsAnyPointsXldmoments_any_points_xld — 被视为点云的轮廓或多边形的任意几何矩。

签名

描述

moments_any_points_xldmoments_any_points_xldMomentsAnyPointsXldMomentsAnyPointsXldMomentsAnyPointsXldmoments_any_points_xld calculates arbitrary moments MMMMmm of the point clouds given by the contours or polygons XLDXLDXLDXLDXLDxld (i.e., the order of the points in the contour or polygon is not taken into account).

The computed moments are normalized depending on the desired mode ModeModeModeModemodemode:

'unnormalized'：

No normalization. The computed moment is:

'unnormalized_central'：

Shift the contour points by their centroid = [CenterRowCenterRowCenterRowCenterRowcenterRowcenter_row, CenterColCenterColCenterColCenterColcenterColcenter_col]:

'normalized'：

Normalization by the area A = AreaAreaAreaAreaareaarea from XLDXLDXLDXLDXLDxld:

'central'：

Normalization by the area A = AreaAreaAreaAreaareaarea and a shift of the contour points by their centroid = [CenterRowCenterRowCenterRowCenterRowcenterRowcenter_row, CenterColCenterColCenterColCenterColcenterColcenter_col]:

For the normalization of the moments three specific values are used: The area AreaAreaAreaAreaareaarea and the coordinates CenterRowCenterRowCenterRowCenterRowcenterRowcenter_row,CenterColCenterColCenterColCenterColcenterColcenter_col of it's centroid (this values can be computed with area_center_points_xldarea_center_points_xldAreaCenterPointsXldAreaCenterPointsXldAreaCenterPointsXldarea_center_points_xld).

If the contour or polygon is closed (end point = start point), the end point of the contour or polygon is not taken into account to avoid that it receives twice the weight of the other points.

moments_any_xldmoments_any_xldMomentsAnyXldMomentsAnyXldMomentsAnyXldmoments_any_xld should be used if the contour XLDXLDXLDXLDXLDxld intersects itself or if it is not possible to close the contour using a line from end to start point without self-intersection, because in this case moments_any_xldmoments_any_xldMomentsAnyXldMomentsAnyXldMomentsAnyXldmoments_any_xld does not produce useful results.可使用 test_self_intersection_xldtest_self_intersection_xldTestSelfIntersectionXldTestSelfIntersectionXldTestSelfIntersectionXldtest_self_intersection_xld 检测轮廓或多边形是否自相交。

If more than one contour or polygon is passed, MMMMmm contains all desired moments of the first contour/polygon followed by all the moments of the second contour/polygon and so forth.

执行信息

• 多线程类型：可重入（与非独占算子并行运行）。
• 多线程作用域：全局（可从任何线程调用）。
• 未采用并行化处理。

参数

复杂度

设 n 为轮廓或多边形的点数。则运行时间为 O(n)。

结果

moments_any_points_xldmoments_any_points_xldMomentsAnyPointsXldMomentsAnyPointsXldMomentsAnyPointsXldmoments_any_points_xld 在输入不为空时返回 2 ( H_MSG_TRUE )。如果输入为空则可设置行为通过 set_system(::'no_object_result',<Result>:)set_system("no_object_result",<Result>)SetSystem("no_object_result",<Result>)SetSystem("no_object_result",<Result>)SetSystem("no_object_result",<Result>)set_system("no_object_result",<Result>)。如有必要，则抛出异常。

可能的前趋

area_center_points_xldarea_center_points_xldAreaCenterPointsXldAreaCenterPointsXldAreaCenterPointsXldarea_center_points_xld, gen_contours_skeleton_xldgen_contours_skeleton_xldGenContoursSkeletonXldGenContoursSkeletonXldGenContoursSkeletonXldgen_contours_skeleton_xld, smooth_contours_xldsmooth_contours_xldSmoothContoursXldSmoothContoursXldSmoothContoursXldsmooth_contours_xld, gen_polygons_xldgen_polygons_xldGenPolygonsXldGenPolygonsXldGenPolygonsXldgen_polygons_xld

替代

moments_points_xldmoments_points_xldMomentsPointsXldMomentsPointsXldMomentsPointsXldmoments_points_xld, moments_any_xldmoments_any_xldMomentsAnyXldMomentsAnyXldMomentsAnyXldmoments_any_xld

另见

moments_points_xldmoments_points_xldMomentsPointsXldMomentsPointsXldMomentsPointsXldmoments_points_xld, area_center_points_xldarea_center_points_xldAreaCenterPointsXldAreaCenterPointsXldAreaCenterPointsXldarea_center_points_xld, moments_region_2ndmoments_region_2ndMomentsRegion2ndMomentsRegion2ndMomentsRegion2ndmoments_region_2nd, area_centerarea_centerAreaCenterAreaCenterAreaCenterarea_center

模块

基础

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