Aggregate point data into grid cells — dgbin

Bins a set of lon/lat points — optionally with associated numeric values — into the cells of a discrete global grid. Returns a data frame (no geometry) with per-cell statistics (equivalent to DGGRID's BIN_POINT_VALS / BIN_POINT_PRESENCE operations).

Usage

dgbin_points(
  dggs,
  lon,
  lat,
  values = NULL,
  output_count = is.null(values),
  output_mean = !is.null(values),
  output_total = FALSE
)

Arguments

dggs: A dggs object from dgconstruct.
lon: Numeric vector of longitudes (decimal degrees).
lat: Numeric vector of latitudes (decimal degrees).
values: Optional numeric vector of values to aggregate (same length as lon/lat). If NULL, only point counts are computed.
output_count: Logical. Return count of points per cell. Default: TRUE when values is NULL, FALSE otherwise.
output_mean: Logical. Return mean of values per cell. Only meaningful when values is supplied. Default: TRUE when values is not NULL.
output_total: Logical. Return total (sum) of values per cell. Only meaningful when values is supplied. Default: FALSE.

Value

A data frame with a seqnum column (cell ID) plus whichever of count, mean, total were requested.

Examples

library(dggridR)
data(dgquakes)
dggs <- dgconstruct(spacing=1000, metric=FALSE, resround='down')
#> Resolution: 3, Area (mi^2): 1173851.79791229, Spacing (mi): 843.496246531419, CLS (mi): 964.285490648183

# Count earthquakes per cell
dgbin_points(dggs, dgquakes$lon, dgquakes$lat) |> head(20)
#>    seqnum count
#> 1       1     1
#> 2       2   701
#> 3       4    35
#> 4       5   257
#> 5       7    68
#> 6       8   190
#> 7      12    51
#> 8      13     3
#> 9      14    94
#> 10     16     2
#> 11     18   202
#> 12     21   195
#> 13     22   210
#> 14     24    89
#> 15     25    11
#> 16     27    49
#> 17     28   974
#> 18     30     8
#> 19     31    48
#> 20     33     1

# Aggregate magnitude per cell
dgbin_points(dggs, dgquakes$lon, dgquakes$lat, values=dgquakes$mag,
             output_count=TRUE, output_total=TRUE) |> head(20)
#>    seqnum count     mean   total
#> 1       1     1 3.400000    3.40
#> 2       2   701 3.674608 2575.90
#> 3       4    35 4.477143  156.70
#> 4       5   257 3.429572  881.40
#> 5       7    68 4.482353  304.80
#> 6       8   190 3.432105  652.10
#> 7      12    51 3.570588  182.10
#> 8      13     3 4.366667   13.10
#> 9      14    94 4.037234  379.50
#> 10     16     2 4.550000    9.10
#> 11     18   202 3.424950  691.84
#> 12     21   195 3.461385  674.97
#> 13     22   210 3.296667  692.30
#> 14     24    89 3.377640  300.61
#> 15     25    11 3.353636   36.89
#> 16     27    49 4.131429  202.44
#> 17     28   974 3.278070 3192.84
#> 18     30     8 3.500000   28.00
#> 19     31    48 4.577083  219.70
#> 20     33     1 4.100000    4.10