Floating point comparison issues with "targets that do not sum to 1" error

[dfeehan]

Great package - thanks!

I've been playing around with it, and I've encountered an issue (maybe a bug?).

It looks like the function check_any_data_issues is looking to see if all of the weighting targets add up to 1. I have a situation where they do all add up to 1, but I'm getting the error message "Target variable ... has targets that do not sum to 1." I suspect this is a floating point comparison issue.

Here's a very small example that should be reproducible (let me know if it doesn't work for you):

atlanta <- structure(list(w_race = c("White", "White", "White", "White", 
"Black", "White", "Black", "White", "Other race", "Black", "White", 
"White", "White", "White", "White", "White", "White", "White", 
"White", "White")), row.names = c(NA, -20L), class = c("tbl_df", 
"tbl", "data.frame"))

(atlanta)
#>        w_race
#> 1       White
#> 2       White
#> 3       White
#> 4       White
#> 5       Black
#> 6       White
#> 7       Black
#> 8       White
#> 9  Other race
#> 10      Black
#> 11      White
#> 12      White
#> 13      White
#> 14      White
#> 15      White
#> 16      White
#> 17      White
#> 18      White
#> 19      White
#> 20      White

targets <- structure(list(variable = c("w_race", "w_race", "w_race"), level = c("Black", 
"Other race", "White"), proportion = c(0.299944881294484, 0.0993062927185731, 
0.600748825986942)), row.names = c(NA, -3L), class = c("tbl_df", 
"tbl", "data.frame"))

(targets)
#>   variable      level proportion
#> 1   w_race      Black 0.29994488
#> 2   w_race Other race 0.09930629
#> 3   w_race      White 0.60074883

sum(targets$proportion)
#> [1] 1

autumn::harvest(atlanta, target = targets)
#> Error in check_any_data_issues(data, target, weights): Errors detected in weight targets:
#> Target variable `w_race` has targets that do not sum to 1.

^{Created on 2020-07-14 by the reprex package (v0.3.0)}

If I'm missing something, please let me know. Thanks again for all of your work on the package.