Returns the scan (scan) from a polar volume (pvol) with elevation angle
closest to elev.
get_scan(x, elev, all = FALSE)A pvol object.
Numeric. Elevation angle in degrees.
Logical. Return the first scan in the pvol object
closest to the requested elevation (FALSE), or a list with
all scans equally close to the requested elevation (TRUE).
A scan object when all equals FALSE (default), or a list of scan objects if all equals TRUE
In cases where elev is exactly in between two
scan elevation angles, the lower elevation angle scan is returned.
# Locate and read the polar volume example file
pvolfile <- system.file("extdata", "volume.h5", package = "bioRad")
pvol <- read_pvolfile(pvolfile)
# Get elevation angles
get_elevation_angles(pvol)
#> [1] 0.5 1.5 2.5
# Extract the scan closest to 3 degrees elevation (2.5 degree scan)
scan <- get_scan(pvol, 3)
# Get summary info
scan
#> Polar scan (class scan)
#>
#> parameters: DBZH VRADH RHOHV ZDR PHIDP
#> elevation angle: 2.5 deg
#> dims: 480 bins x 360 rays
# Extract all scans closest to 3 degrees elevation (2.5 degree scan)
# Always returns a list with scan object(s), containing multiple scans
# if the pvol contains multiple scans at the same closest elevation.
scan_list <- get_scan(pvol, 3)
scan_list
#> Polar scan (class scan)
#>
#> parameters: DBZH VRADH RHOHV ZDR PHIDP
#> elevation angle: 2.5 deg
#> dims: 480 bins x 360 rays