我正在使用`igraph`在R中绘制网络图。该网络有1,380个节点和约150k条边。下面是来自`igraph`的摘要:
IGRAPH UN-- 1380 159718 --
+ attr: name (v/c), rels (v/n), label (v/n), degree (v/n), btw (v/n), color (v/c), rels (e/n)
我正在尝试添加一个颜色渐变,根据节点的中心性对其进行着色。我尝试了几个不同版本的代码,首先是来自这个示例的代码:
# calculate betweenness
V(g_yearly)$btw <- betweenness(g_yearly)
# construct color palette
fine <- 100
palette <- colorRampPalette(c('blue','green'))
# assign palette to nodes
V(g_yearly)$color <- palette(fine) [as.numeric(cut(V(g_yearly)$btw,breaks=fine))]
# plot network
plot.igraph(g_yearly,vertex.shape="circle",vertex.size=1,vertex.label.cex=0.6,layout=lgl(g_yearly),edge.arrow.size=0,edge.width=E(g_yearly)$rels/50)
我遇到了以下错误和追踪信息:
Error in seq.int(0, 1, length.out = n) :
'length.out' must be a non-negative number
9 .approxfun(x, y, v, method, yleft, yright, f)
8 palette[[1L]](x)
7 cbind(palette[[1L]](x), palette[[2L]](x), palette[[3L]](x), if (alpha) palette[[4L]](x))
6 pmin(rgb, 1)
5 pmax(pmin(rgb, 1), 0)
4 roundcolor(cbind(palette[[1L]](x), palette[[2L]](x), palette[[3L]](x),
if (alpha) palette[[4L]](x)))
3 ramp(seq.int(0, 1, length.out = n))
2 palette(palette)
1 plot.igraph(g_yearly, vertex.shape = "circle", vertex.size = 1,
vertex.label.cex = 0.6, layout = layout.lgl(g_yearly), edge.arrow.size = 0,
edge.width = E(g_yearly)$rels/50)
In addition: Warning message:
In .approxfun(x, y, v, method, yleft, yright, f) :
NAs introduced by coercion
如果我使用
rainbow
函数,这将完美运作:V(g_yearly)$color <- rainbow(V(g_yearly)$btw,start=3/6,end=4/6)
奇怪的是,当我第一次运行代码后,似乎无法在网络上运行plot而不出现相同的错误 - 即使我删除对palette
的调用。
我在使用palette
方面做错了什么?