makePolarGrid: Make a grid of segments.

In GastonMauroDiaz/caiman: Canopy Image Analysis

Description

Partitioning the hemisphere into segments of equal angular resolution for both zenith and azimuth angles.

Usage

makePolarGrid(
  z,
  a = makeAimage(z),
  angleWidth = asAngle(1),
  sequential = FALSE
)

## S4 method for signature 'ZenithImage'
makePolarGrid(
  z,
  a = makeAimage(z),
  angleWidth = asAngle(1),
  sequential = FALSE
)

Arguments

z	ZenithImage.
a	AzimuthImage.
angleWidth	Angle. It must be 30, 15, 10, 7.5, 6, 5, 3.75, 3, 2.5, 1.875, 1 or 0.5 degrees. This values could divide both 0-360 and 0-90 into a whole number of segments.
sequential	logical. If it is TRUE the segments are labeled with sequential numbers. By default (FALSE), labeling numbers are not sequential (see Details).

Details

Intersecting rings with sectors makes a grid in which each segment is a portion of the hemisphere. Each pixel of the grid is labeled with an ID that codify both ring and sector ID. For example, a grid with a regular interval of 1 degree has segment from 1001 to 360090. This numbers are calculated with: sectorID x 1000 + ringsID, where sectorID is the ID number of the sector and ringsID is the ID number of the ring.

Value

PolarSegmentation.

See Also

makeZimage, makeAimage, makePolarSectors, makeRings.

Examples

z <- makeZimage(480, lensPolyCoef())
a <- makeAimage(z)
g <- makePolarGrid(z, a, angleWidth = asAngle(10))
g
head(levels(g)[[1]])
plot(g)

GastonMauroDiaz/caiman documentation built on Jan. 22, 2022, 4:43 a.m.