R/surveyPlanning.R
centreLawnOnPosition.Rd
Centres a regular rectangular survey on a desired latitude and longitude
centreLawnOnPosition(centreLon, centreLat, proj4string = NULL, tolerance = 20, ...)
centreLon | Desired centre location of survey |
---|---|
centreLat | Desired centre location of survey |
proj4string | projection string of class CRS-class. If NULL defaults to "+proj=longlat +datum=WGS84" |
tolerance | maximum distance (in metres) between desired survey centre and realised survey centre |
... | other arguments to be passed into lawnSurvey |
Line transect coordinates (lon, lat) as specified in lawnSurvey
# NOT RUN { coords=centreLawnOnPosition(centreLon=-170,centreLat=-60,lineLengthkm=2,lineSpacingkm=0.5, startBearingdeg=30,numOfLines=5) plot(0,0,xlim=range(coords[,1]),ylim=range(coords[,2]),type='n', xlab='Longitude, deg',ylab='Latitude, deg') arrows(x0=coords[1:(nrow(coords)-1),1], y0=coords[1:(nrow(coords)-1),2], x1 = coords[2:nrow(coords),1], y1 = coords[2:nrow(coords),2]) text(coords,row.names(coords),cex=0.6) points(coords[1,1],coords[1,2],col='blue',pch=17,cex=2) points(coords[nrow(coords),1],coords[nrow(coords),2],col='blue',pch=15,cex=2) points(-170,-60,col='purple',pch=19,cex=2) points(geomean(coords),col='red',pch=19,cex=1) legend('bottomright',c('Beginning','End','Desired centre','Actual centre'), col=c('blue','blue','purple','red'),pch=c(17,15,19,19),pt.cex=c(1,1,2,1)) # }