quadscheme.lt: Create line transect quadrature for spatstat
Description
Creates a quadrature for spatstat from a study area, observations, and lines
Usage
quadscheme.lt(study.area, observations, lines, width = NULL, epsvu = c(1, 0.01), show.warnings=FALSE)
Arguments
study.area
owin class giving the boundaries of the study area
observations
- data frame of observations with the following structure
label - label linking it to a unique line
x - x coordinate
y - y coordinate
distance- perpendicular distance from center line
... - any number of covariates
lines
- data frame of lines with the following structure
label - unique label
x0 - x coordinate of beginning of line
y0 - y coordinate of beginning of line
x1 - x coordinate of end of line
y1 - y coordinate of end of line
width - optional full width of transect around line
angle - angle of rotation to get to vertical
... - any number of covariates
width
if no width field is given in lines then it must be specified here
as a constant width for all lines
epsvu
pixel dimensions epsvu[1] in v direction (height) and epsvu[2] in
u direction (width) (these are used once line is rotated vertically.
show.warnings
if TRUE, warnings from quadrature construction will be
shown.
Value
- Q
- quadscheme as defined in spatstat
- transects
- list of transect polygon dataframes
- lines.psp
- line segment process