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raster::erase函数-RGEOSBinTopoFunc:TopologyException中出错

rgeo-shapefile r-raster raster r

0

string · 技术社区 · 6 年前

我正在使用光栅包擦除功能,就像我之前发布的剪切和溶解重叠多边形的解决方案一样- Dissolve Overlapping Polygons using difference and union in R

对于一些多边形,我得到了下面的erase函数错误:

RGEOSBinTopoFunc中出错(spgeom1、spgeom2、byid、id、drop_lower_td、unaryUnion_如果byid_false,: 地形异常:输入几何1无效:点1.1197332302192855 47.203098020153668处或附近的自交点1.1197332302192855 47.203098020153668

library(raster)
library(rgeos)
library(sp)

fields <- gBuffer(fields, byid=TRUE, width=0) # Expands the given geometry to include 
the area within the specified width 

zone <- fields[fields$Type == "Zone", ]
plot <- fields[fields$Type == "Plot", ]

d <- erase(zone, plot) #issue here
spplot(d, "Rx")

# I tried using rgeos::gBuffer to avoid RGEOSBinTopology Exception but it did not worked out. Any guidance in this area would be really helpful.

zone <- gBuffer(zone, byid=TRUE, width=0)
plot <- gBuffer(plot, byid=TRUE, width=0)

0 回复 | 直到 6 年前

1

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Robert Hijmans 6 年前

绘图多边形非常混乱。即使它们是有效的。问题出现在 erase 它变成了聚合(“分解”)的论点 y (“字段”),但这会生成无效的拓扑。我需要研究如何捕捉到最好的效果,但是,现在(可能还有一段时间),这里有一个使用cleangeo的解决方案,但是你可能想使用一个工具来清理多边形(捕捉顶点)——也许是使用Rmapshaper?

library(raster)
library(rgeos)

f <- "WUERZ-I-WW _ Plot _TrialMap.shp"
fields = shapefile(f)
zone <- fields[fields$Type == "Zone", ]
plot <- fields[fields$Type == "Plot", ]

aplot <- aggregate(plot)
rgeos::gIsValid(aplot)
#[1] FALSE
#Warning message:
#In RGEOSUnaryPredFunc(spgeom, byid, "rgeos_isvalid") :
#  Self-intersection at or near point 13.033265979999999 51.190776640000003

library(cleangeo)
cplot <- clgeo_Clean(aplot)
rgeos::gIsValid(cplot)
# TRUE

d <- erase(zone, cplot)