r - sp::over() for point in polygon analysis

Question

I have a shapefile named "ind_adm" and a SpatialPointsDataFrame called "pnts". The "pnts" contains points generated at random, and some of the points overlap with the polygon. See picture below.

Now, I want do do a point in polygon analysis, i.e. I want to find out which points lie inside the gray polygon representing the boundary of India. For this I am using the over() function in the sp library.

pt.in.poly <- sp::over(ind_adm, pnts, fn = mean) #do the join

However, the output I am getting is

    >pt.in.poly
    values
    0 6.019467

I should actually get the index of the points that are "in" the polygon.

Where am I going wrong?

Answer 1

Found this concise and intuitive syntax for over:

   pnts[ind_adm,] 

from this Intro document