vp)R base functions for inspecting a vertical profile of biological targets
(vp) object.
# S3 method for vp
summary(object, ...)is.vp(x)
# S3 method for vp
dim(x)
A vp object.
Additional arguments affecting the summary produced.
A vp object.
For is.vp(): TRUE for an object of class vp, otherwise
FALSE.
For dim.vp(): number of heights and quantities in a vertical
profile (vp).
NA: Maps to nodata in the ODIM convention: value to denote areas void
of data (never radiated).
NaN: Maps to undetect in the ODIM convention: denote areas below the
measurement detection threshold (radiated but nothing detected). The value is
also used when there are too few datapoints to calculate a quantity.
0: Maps to 0 in the ODIM convention: denote areas where the quantity
has a measured value of zero (radiated and value zero detected or inferred).
It depends on a radar's detection threshold or signal to noise ratio whether
it safe to assume an undetect is equivalent to zero. When dealing with
close range data only (within 35 km), it is typically safe to assume aerial
densities (dens) and reflectivities (eta) are in fact zero in case of
undetects.
A vertical profile of biological targets contains a collection of quantities,
organized in different (typically equally spaced) altitude layers (height
bins) above the earth's surface. A vertical profile (vp) object is a list
containing:
radar: Radar identifier.
datetime: Nominal time of the volume to which the scan belongs in UTC.
data: A data.frame with the profile's quantities organized per height
bin. Use get_quantity() to access these:
height: Height bin (lower bound) in m above sea level.
u: Speed component west to east in m/s.
v: Speed component north to south in m/s.
w: Vertical speed (unreliable!) in m/s.
ff: Horizontal speed in m/s.
dd: Direction in degrees clockwise from north.
sd_vvp: VVP radial velocity standard deviation in m/s.
gap: Angular data gap detected in T/F.
dbz: Animal reflectivity factor in dBZ.
eta: Animal reflectivity in cm^2/km^3.
dens: Animal density in animals/km^3.
DBZH: Total reflectivity factor (bio + meteo scattering) in dBZ.
n: Number of data points used for the ground speed estimates
(quantities u, v, w, ff, dd).
n_all: Number of data points used for the radial velocity standard
deviation estimate (quantity sd_vvp).
n_dbz: Number of data points used for reflectivity-based estimates
(quantities dbz, eta, dens).
n_dbz_all: Number of data points used for the total reflectivity
estimate (quantity DBZH).
attributes: List of the vertical profile's what, where and how
attributes.
# NOT RUN {
# Load the example vertical profile
vp <- example_vp
# Verify that it is an object of class vp
is.vp(vp)
# Get summary info
vp # Same as summary(vp) or print(vp)
# Get dimensions
dim(vp)
# }
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