# gridweights

0th

Percentile

##### Compute Quadrature Weights Based on Grid Counts

Computes quadrature weights for a given set of points, using the counting weights'' for a grid of rectangular tiles.

Keywords
spatial
##### Usage
gridweights(X, ntile, ..., window=NULL, verbose=FALSE)
##### Arguments
X
Data defining a point pattern.
ntile
Number of tiles in each row and column of the rectangular grid. An integer vector of length 1 or 2.
...
Ignored.
window
Default window for the point pattern
verbose
Logical flag. If TRUE, information will be printed about the computation of the grid weights.
##### Details

This function computes a set of quadrature weights for a given pattern of points (typically comprising both data'' and dummy'' points). See quad.object for an explanation of quadrature weights and quadrature schemes.

The weights are computed by the `counting weights'' rule based on a regular grid of rectangular tiles. First X and (optionally) window are converted into a point pattern object. Then the bounding rectangle of the window of the point pattern is divided into a regular ntile[1] * ntile[2] grid of rectangular tiles. The weight attached to a point of X is the area of the tile in which it lies, divided by the number of points of X lying in that tile.

##### Value

• Vector of nonnegative weights for each point in X.