R vertex.pie错误：“ length.out”必须为非负数

Question

我正在尝试在每个顶点上制作一个饼图，并带有度数和度数值。

pie.vals <- lapply((1:vcount(cMatrix)),function(i) c(in.flow[i]/1000000, abs(out.flow[i])/1000000))

要在每个顶点上绘制饼图：

plot(cMatrix, layout=l,vertex.size = vsize, vertex.shape = "pie", vertex.pie = pie.vals, edge.width = ewidth, edge.arrow.size =0.1)

我一直遇到以下错误：

  

seq.int（values [i]，values [i + 1]，length.out = n）中的错误：   “ length.out”必须为非负数

pie.vals如下所示似乎没有错：

[[1]]
   A        A 
6.262598 2.736474 

[[2]]
   B        B 
13.32933 13.32933 

[[3]]
   C        C 
17.41709 17.41709 

 [[4]]
    D         D 
 4.318938 10.350361 

  [[5]]
  E       E 
  19.5844 19.5844 

 [[6]]
   F        F 
 6.997959 6.486245 

 [[7]]
   G        G 
 16.68075 16.68075 

 [[8]]
   H        H 
  6.087895 4.094310 

 [[9]]
  I I 
  0 0 

 [[10]]
  J J 
  0 0 

 [[11]]
  K K 
  0 0 

 [[12]]
  L L 
  0 0 

 [[13]]
 M M 
 0 0 

  [[14]]
  N N 
  0 0 

  [[15]]
   O O 
   0 0 

   [[16]]
   P P 
   0 0 

   [[17]]
   Q Q 
   0 0