Error in triangulationBlobs due to uncoordinated points

[drserajames]

If there's a line of <10s in the HI table, then triangulationBlobs gives the error below:

> set.seed(54743)
> hi <- matrix(10*2^sample(1:10, 25, replace=T), ncol=5)
> hi[1,] <- "<10"
> hi
     [,1]   [,2]   [,3]    [,4]    [,5]   
[1,] "<10"  "<10"  "<10"   "<10"   "<10"  
[2,] "20"   "80"   "40"    "5120"  "10240"
[3,] "40"   "160"  "10240" "640"   "640"  
[4,] "1280" "160"  "20"    "10240" "80"   
[5,] "5120" "2560" "320"   "80"    "160"  
> map <- make.acmap(hi, options = list(ignore_disconnected = TRUE))
a
Took 0.02 secs

> tri <- triangulationBlobs(map)
a
Error in attr(blob, "volume") <- sum(grid_values <= value_lim) * gridsize^ndims : 
  attempt to set an attribute on NULL