R base functions for inspecting a plan position indicator (ppi
) object.
For is.ppi()
: TRUE
for an object of class ppi
, otherwise
FALSE
.
For dim.ppi()
: number of parameters (param
), x and y pixels in a
plan position indicator (ppi
).
A plan position indicator is a projection of radar data onto the earth's
surface, generated from a single scan (scan
) with project_as_ppi()
, a
polar volume (pvol
) with integrate_to_ppi()
or multiple plan position
indicators (ppi
) with composite_ppi()
. A plan position indicator (ppi
)
object is a list containing:
radar
: Radar identifier.
datetime
: Nominal time of the volume to which the scan belongs in UTC.
data
: A sp::SpatialGridDataFrame
containing the georeferenced data.
See summary.param()
for commonly available parameters, such as DBZH
.
geo
: List of the scan's geographic properties (see the geo
element in
summary.scan()
), with two additional properties:
bbox
: Bounding box for the plan position indicator in decimal degrees.
merged
: Logical. Flag to indicate if a plan position indicator is a
composite of multiple scans. TRUE
if generated with integrate_to_ppi()
or composite_ppi()
.
# Project a scan as a ppi
ppi <- project_as_ppi(example_scan)
# Check if it is an object of class ppi
is.ppi(ppi)
#> [1] TRUE
# Get summary info
ppi # Same as summary(ppi) or print(ppi)
#> Plan position indicator (class ppi)
#>
#> parameters: DBZH VRADH RHOHV ZDR PHIDP
#> dims: 201 x 201 pixels
#>
# Get dimensions
dim(ppi)
#> [1] 5 201 201