rpolygonspotfireterr

Creating ellipses based on coordinates and area with R to plot on map


How can I create, using R, ellipse polygons from a dataframe containing x, y, and z, Orientation, and Ratio columns? What R packages and functions could I look at to accomplish this?

I would also like to calculate the overlapping area when ellipses overlap each other.

Data input description:

x,y : geocoordinates that I have already transformed from lat/long into the appropriate projection system, the ellipse would be centered around this point

z: area, in square feet, of the ellipse

Orientation: The orientation of the ellipse (i.e. 70 degrees from north)

Ratio: Aspect ratio of the ellipse (i.e. 3:1 Length:Width would mean length is 3X the width)

Trying to do this in R, TERR, and spotfire, to plot the ellipses on a map. Thanks for any and all help!


Solution

  • You could try the ellipse R package. https://cran.r-project.org/web/packages/ellipse/ellipse.pdf

    qGIS is an opensource version arcGIS and might be something you'd look at if you're doing alot of spatial analysis.