Let us consider a set of a 2-D points (longitude, latitude) each of which is centre of square grid (intersect point of the diagonals of the square).
I try to make you understand what I want to do in a graphical manner.
Sample data (point set):
lon<-c(88.56630, 88.62501, 88.60013, 88.57499, 88.65879, 88.63392, 88.60879)
lat<- c(21.03517, 21.01287, 21.05434, 21.09610, 21.03207, 21.07354, 21.11531)
Plots:
Figure 1: First one is the scatter plot of the point set.
Figure 2: All the points are bilinear (this is known).
Figure 3: Each point is centre of a square of size (approx.) 4km by 4km (we need construct those squares from the given centre point).
Figure 4: This is what I want to have, The polygon obtained by the outer sides of the squares (black lines).
Note: I have lots of point sets of arbitrary shapes like the above sample with maximum cardinality of the sets as 100.
How can this get this polygon (no hole)?