View source: R/spatial_weights.R
weighted_spatial_adjacency | R Documentation |
Constructs a spatial adjacency matrix, where weights are determined by a secondary feature matrix.
weighted_spatial_adjacency(
coord_mat,
feature_mat,
wsigma = 0.73,
alpha = 0.5,
nnk = 27,
weight_mode = c("binary", "heat"),
sigma = 1,
dthresh = sigma * 2.5,
include_diagonal = TRUE,
normalized = FALSE,
stochastic = FALSE
)
coord_mat |
A matrix with the spatial coordinates of the data points, where each row represents a point and each column represents a coordinate dimension. |
feature_mat |
A matrix with the feature vectors of the data points, where each row represents a point and each column represents a feature dimension. The number of rows in feature_mat must be equal to the number of rows in coord_mat. |
wsigma |
The spatial weight scale (default: 0.73). |
alpha |
The mixing parameter between 0 and 1 (default: 0.5). A value of 0 results in a purely spatial adjacency matrix, while a value of 1 results in a purely feature-based adjacency matrix. |
nnk |
The number of nearest neighbors to consider (default: 27). |
weight_mode |
The mode to use for weighting the adjacency matrix, either "binary" or "heat" (default: "binary"). |
sigma |
The bandwidth for heat kernel weights (default: 1). |
dthresh |
The distance threshold for nearest neighbors (default: sigma * 2.5). |
include_diagonal |
A logical value indicating whether to include diagonal elements in the adjacency matrix (default: TRUE). |
normalized |
A logical value indicating whether to normalize the adjacency matrix (default: FALSE). |
stochastic |
A logical value indicating whether to make the resulting adjacency matrix doubly stochastic (default: FALSE). |
A sparse adjacency matrix with weighted spatial relationships.
coord_mat <- as.matrix(expand.grid(x=1:9, y=1:9, z=1:9))
fmat <- matrix(rnorm(nrow(coord_mat) * 100), nrow(coord_mat), 100)
wsa1 <- weighted_spatial_adjacency(coord_mat, fmat, nnk=3, weight_mode="binary", alpha=1, stochastic=TRUE)
wsa2 <- weighted_spatial_adjacency(coord_mat, fmat, nnk=27, weight_mode="heat", alpha=0, stochastic=TRUE, sigma=2.5)
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.