formatDistData(), The distances must be numeric

Question

This question might have been repeated. But even after going through the previous links, I am not able to solve this.

I am trying to use the formatDistData() function from the unmarked package, however, when running the code

yDat <- formatDistData(Detects1, distCol="distance", transectNameCol="transect", dist.breaks=db)

I get an error saying "The distances must be numeric". I have already ran the as.numeric() function but the code displays the same error.

Here is how my data looks. I have transect in one column and distance in the other. On the right you can see that distance is a num value and transect is chr. If someone is able to tell me what I need to do in order for it to work that would be great

Data

transect,distance
NT1,14
NT1,14
NT1,20
NT1,20
NT1,10
NT1,15






> dput(Detects1)`
structure(list(transect = c("NT1", "NT1", "NT1", "NT1", "NT1", 
"NT1", "NT1", "NT1", "NT1", "NT1", "NT2", "NT2", "NT2", "NT2", 
"NT2", "NT2", "NT2", "NT2", "NT2", "NT2", "NT2", "NT2", "NT3", 
"NT3", "NT3", "NT3", "NT3", "NT3", "NT3", "NT3", "NT3", "NT3", 
"NT3", "NT3", "NT3", "NT3", "NT3", "NT3", "NT4", "NT3", "NT4", 
"NT4", "NT4", "NT5", "NT5", "NT5", "NT5", "NT5", "SCC1", "SCC1", 
"SCC1", "SCC1", "SCC1", "SCC1", "SCC1", "SCC1", "SCC3", "SCC3", 
"SCC4", "SCC4", "SCC4", "SCC4", "SCC4", "SCC5", "SCC5", "SCC5", 
"SCC5", "SCC5", "SCC5", "SCC5", "Urban1", "Urban1", "Urban1", 
"Urban2", "Urban2", "Urban2", "Urban2", "Urban2", "Urban2", "Urban2", 
"Urban4", "Urban4"), distance = c(14, 14, 20, 20, 10, 15, 5, 
10, 15, 6, 10, 5, 5, 40, 7, 7, 5, 5, 12, 12, 2, 2, 5, 16, 6, 
13, 3, 7, 5, 2, 0, 16, 10, 20, 20, 15, 10, 11, 17, 17, 12, 5, 
3, 5, 8, 21, 12, 12, 15, 15, 7, 12, 3, 5, 6, 3, 2, 7, 8, 21, 
5, 5, 11, 4, 12, 2, 1, 2, 5, 14, 10, 8, 3, 3, 11, 4, 9, 3, 7, 
5, 2, 7)), .Names = c("transect", "distance"), row.names = c(NA, 
-82L), spec = structure(list(cols = structure(list(transect =
structure(list(), class = c("collector_character", 
"collector")), distance = structure(list(), class = c("collector_number", 
"collector"))), .Names = c("transect", "distance")), default =
structure(list(), class = c("collector_guess", 
"collector"))), .Names = c("cols", "default"), class = "col_spec"), class =
c("tbl_df", "tbl", "data.frame"))

Answer 1

The dput output shows me that you are providing a tbl_df (a tidyverse tibble) rather than a standard data.frame. It seems that formatDistData chokes on tibbles. If you do:

library(unmarked)
yDat <- formatDistData(
  as.data.frame(Detects1), # coerce to standard data.frame
  distCol="distance", 
  transectNameCol="transect", 
  dist.breaks = quantile(Detects1$distance, seq(0.1, 0.9, by = 0.1)))

It will work.

Note that you did not provide db, so I used quantile to define arbitrary breaks for the example to work.