Heatmaps
Given two matrices, this function plots heatmaps for each one with a fixed colour scale to allow for comparison.
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heatmap_scale = function(matrix1, matrix2, main1 = NULL, main2 = NULL){
global_min <- min(matrix1, matrix2)
global_max <- max(matrix1, matrix2)
my_palette <- colorRampPalette(c("blue", "white", "red"))(n = 299)
heatmap(matrix1, Colv = NA, Rowv = NA, scale = "none",
col = my_palette, breaks = seq(global_min, global_max, length.out = 300), main = main1)
heatmap(matrix2, Colv = NA, Rowv = NA, scale = "none",
col = my_palette, breaks = seq(global_min, global_max, length.out = 300), main = main2)
}
Quick heatmap plot in R:
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heatmap(matrix, Colv = NA, Rowv = NA, scale = "none")
Eigen-analysis
Plot eigen values of covariance matrix
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plot_eig_values = function(x, main = NULL){
cov_d = (1/nrow(x)) * ( t(x) %*% x )
cov_d_eig = eigen(cov_d)
plot(cov_d_eig$values, main = main)
}
Max index of matrix
Get the row and column number of largest element of matrix
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max_ind = function(mat){
max_index <- which(mat == max(mat), arr.ind = TRUE)
max_index
}