Digits with `geojson_list()`
josiekre opened this issue · 16 comments
There does not seem to be control over the number of digits output when passing a data frame to geojson_list(). No matter how many significant digits there are in the lon and lat columns, the resulting list has at most five digits to the right of the decimal, e.g. -77.11739, 38.94512.
I see from #96 that digits were thought about at some point, but I'm not seeing how this translates into geojson_list(). What am I missing?
Thanks.
Session Info
> devtools::session_info()
Session info -----------------------------------------------------------------------------------
setting value
version R version 3.4.2 (2017-09-28)
system x86_64, darwin15.6.0
ui RStudio (1.1.383)
language (EN)
collate en_US.UTF-8
tz Europe/Copenhagen
date 2018-08-20
Packages ---------------------------------------------------------------------------------------
package * version date source
assertthat 0.2.0 2017-04-11 CRAN (R 3.4.0)
base * 3.4.2 2017-10-04 local
bindr 0.1.1 2018-03-13 cran (@0.1.1)
bindrcpp * 0.2.2 2018-03-29 cran (@0.2.2)
citycastgtn * 0.0.0.9000 <NA> local
cli 1.0.0 2017-11-05 CRAN (R 3.4.2)
commonmark 1.4 2017-09-01 CRAN (R 3.4.1)
compiler 3.4.2 2017-10-04 local
crayon 1.3.4 2017-09-16 CRAN (R 3.4.1)
curl 3.0 2017-10-06 CRAN (R 3.4.2)
datasets * 3.4.2 2017-10-04 local
devtools 1.13.4 2017-11-09 CRAN (R 3.4.2)
digest 0.6.15 2018-01-28 cran (@0.6.15)
dplyr 0.7.6 2018-06-29 cran (@0.7.6)
foreign 0.8-69 2017-06-22 CRAN (R 3.4.2)
geojson 0.2.0 2017-11-08 CRAN (R 3.4.2)
geojsonio 0.5.0.9100 2018-03-22 Github (ropensci/geojsonio@5c39fe7)
glue 1.3.0 2018-07-17 cran (@1.3.0)
graphics * 3.4.2 2017-10-04 local
grDevices * 3.4.2 2017-10-04 local
grid 3.4.2 2017-10-04 local
hms 0.3 2016-11-22 CRAN (R 3.4.0)
httr 1.3.1 2017-08-20 CRAN (R 3.4.1)
jqr 1.0.0 2017-09-28 CRAN (R 3.4.2)
jsonlite 1.5 2017-06-01 CRAN (R 3.4.0)
jsonvalidate 1.0.0 2016-06-13 CRAN (R 3.4.0)
lattice 0.20-35 2017-03-25 CRAN (R 3.4.2)
lazyeval 0.2.1 2017-10-29 CRAN (R 3.4.2)
lubridate 1.7.4 2018-04-11 CRAN (R 3.4.4)
magrittr * 1.5 2014-11-22 CRAN (R 3.4.0)
maptools 0.9-2 2017-03-25 cran (@0.9-2)
memoise 1.1.0 2017-04-21 CRAN (R 3.4.0)
methods * 3.4.2 2017-10-04 local
pillar 1.1.0 2018-01-14 cran (@1.1.0)
pkgconfig 2.0.1 2017-03-21 CRAN (R 3.4.0)
purrr 0.2.4 2017-10-18 CRAN (R 3.4.2)
R6 2.2.2 2017-06-17 CRAN (R 3.4.0)
Rcpp 0.12.18 2018-07-23 cran (@0.12.18)
readr 1.1.1 2017-05-16 CRAN (R 3.4.0)
rgdal 1.2-18 2018-03-17 cran (@1.2-18)
rgeos 0.3-26 2017-10-31 cran (@0.3-26)
RJSONIO 1.3-0 2014-07-28 CRAN (R 3.4.0)
rlang 0.2.1.9000 2018-07-30 Github (r-lib/rlang@d97e73d)
roxygen2 6.0.1 2017-02-06 CRAN (R 3.4.0)
rstudioapi 0.7 2017-09-07 CRAN (R 3.4.1)
sp 1.3-1 2018-06-05 cran (@1.3-1)
stats * 3.4.2 2017-10-04 local
stringi 1.2.2 2018-05-02 cran (@1.2.2)
stringr 1.3.1 2018-05-10 cran (@1.3.1)
tibble 1.4.2 2018-01-22 CRAN (R 3.4.3)
tidyr 0.8.0 2018-01-29 cran (@0.8.0)
tidyselect 0.2.4 2018-02-26 cran (@0.2.4)
tools 3.4.2 2017-10-04 local
utf8 1.1.3 2018-01-03 cran (@1.1.3)
utils * 3.4.2 2017-10-04 local
V8 1.5 2017-04-25 CRAN (R 3.4.0)
withr 2.1.2 2018-05-02 Github (jimhester/withr@79d7b0d)
xml2 1.2.0 2018-01-24 cran (@1.2.0)
yaml 2.1.19 2018-05-01 cran (@2.1.19) Here is a simple example:
> (s <- dplyr::data_frame(
id = c("A", "B"),
lat = c(38.949019, 39.008222),
lon = c(-77.080369, -76.780363)
))
# A tibble: 2 x 3
id lat lon
<chr> <dbl> <dbl>
1 A 38.9 -77.1
2 B 39.0 -76.8
Let's print out the lon column from the data frame to make sure all the digits we put in are still there. We are looking for 6 digits after the decimal and 6 come out:
> format(s$lon, digits = 10)
[1] "-77.080369" "-76.780363"
Now we'll convert it.
> (g <- geojsonio::geojson_list(s, lat = "lat", lon = "lon"))
$type
[1] "FeatureCollection"
$features
$features[[1]]
$features[[1]]$type
[1] "Feature"
$features[[1]]$geometry
$features[[1]]$geometry$type
[1] "Point"
$features[[1]]$geometry$coordinates
[1] -77.08037 38.94902
$features[[1]]$properties
$features[[1]]$properties$id
[1] "A"
$features[[2]]
$features[[2]]$type
[1] "Feature"
$features[[2]]$geometry
$features[[2]]$geometry$type
[1] "Point"
$features[[2]]$geometry$coordinates
[1] -76.78036 39.00822
$features[[2]]$properties
$features[[2]]$properties$id
[1] "B"
attr(,"class")
[1] "geo_list"
attr(,"from")
[1] "data.frame"
Now when we look again, we have lost a digit (5 instead of 6):
> is(g$features[[1]]$geometry$coordinates)
[1] "numeric" "vector"
> format(g$features[[1]]$geometry$coordinates, digits = 10)
[1] "-77.08037" " 38.94902"
one thing is that you're on an older dev version, we're currently on 0.6.0.9100, though I don't think that affects the issue at hand.
have you played with the digits option in R? you can get it by getOption('digits') and set it by options(digits = 8)
options(digits = 8)
s <- dplyr::data_frame(
id = c("A", "B"),
lat = c(38.949019, 39.008222),
lon = c(-77.080369, -76.780363)
)
(g <- geojsonio::geojson_list(input = s, lat = "lat", lon = "lon"))
lapply(g$features, "[[", c("geometry", "coordinates"))
#> [[1]]
#> [1] -77.080369 38.949019
#>
#> [[2]]
#> [1] -76.780363 39.008222let me know what you think
I thought I played with that. In the file output (as opposed to interactive output), I don't think it made a difference. But I will rerun and report back in a couple days. Thx @sckott.
A call to options(digits = 8) does impact the writing out, but I cannot figure out the relationship between that and digits in the call to geojson_list(). Can you elaborate on that?
Sorry for the delay @josiekre - was on vacation.
The number of digits written to the console depends on the R option digits, so you can set that outside of the geojsonio package yourself and it affects what geojson_list() returns. Does that make sense?
I personally think it would be nicer to control the output digits within the function call. It would be better to create a controlled, repeatable function call. I think of options() as things that impact my current R session interactively.
It could be smart to default like this:
geojson_list(..., digits = options('digits')$digits)
@josiekre I've experimented with this. there's no way I can see to allow the user to change digits in the outupt, AND not effect the global digits option.
You can format numbers directly with e.g., format, sprintf, etc. but we can't feasibly do that with the complex nested lists, etc. we're dealing with.
I think the best option is to document that if you want to change digits, set them with options(digits = x). Does that sound okay?
The jsonlite::toJSON() function has a digits option that works in this manner. Have you seen this?
@sckott I might have a simple solution by updating geojson_rw to take precision as a variable since it is used in geojson_write which is called by geojson_rw. I already have the code updated and it works for my use case. I can submit a PR if you think it would be useful for others and not break anything anywhere else. In my testing, it hasn't affected anything else that I have noticed.
thanks @ChrisJones687 ! a PR would be great.
So the PR #152 added ability to manipulate digits for sp class objects, but we don't have a solution for data.frame's, vectors, lists, etc.
I tried using sf internally with data.frames just to see if it would be feasible, but its much slower than what we have now. Oh, and I didn't even check that we can manipulate precision through this route, but I assume we can. Anyway ...
geojson_list_data.frame <- function(input, lat = NULL, lon = NULL, group = NULL,
geometry = "point", type = "FeatureCollection", ...) {
tmp <- guess_latlon(names(input), lat, lon)
out <- list()
for (i in seq_len(NROW(input))) {
out[[i]] <- sf::st_point(as.numeric(c(input[i, tmp$lat], input[i, tmp$lon])))
}
tfile <- tempfile(fileext = ".geojson")
tmpsf <- sf::st_as_sf(input, coords = c("lat", "long"))
sf::st_write(tmpsf, tfile, quiet = TRUE)
xx <- as.geo_list(jsonlite::fromJSON(readLines(tfile), TRUE, FALSE, FALSE),
"data.frame")
xx$features <- lapply(xx$features, function(z) {
z$geometry$coordinates <- rev(as.numeric(z$geometry$coordinates))
z
})
xx$name <- NULL
return(xx)
}