Barry Rowlingson пишет: > Evgeniy Kachalin wrote: > >> What is ability in R to graphically (per mouse) define some area and >> to select all the cases felt in it? >> >> 'identify' is OK for 5-10 cases, but what if cases=1000? > > > You can use 'locator' to let the user click a number of points to > define a polygon, and then use one of the point-in-polygon functions > provided by one of the spatial packages to work out whats in your polygon. > > Look at splancs, spatstat, sp - pretty much anything beginning with > 'sp' - on CRAN. > > In splancs you can just do: > > poly = getpoly() > > - which lets the user draw a polygon on screen, then: > > inPoly = inpip(xypts,poly) > points(xypts[inpip,], pch=19,col="red") > > and that will plot the selected points in solid red dots. > > I don't think there's a way to draw a freehand figure on an R plot, you > have to go click, click, click, and draw straight lines. >
I don't get what is 'xypts' in this case... One step earlier i've plotted plot(y~x,data=dat). What is xypts? -- Evgeniy Kachalin ______________________________________________ [email protected] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
