ggmatrix has been deprecated, and some functions have been merged into ggcor. Please use ggcor instead.
You can install ggmatrix from Github with:
# install.packages("devtools")
devtools::install_github("houyunhuang/ggmatrix")
library(ggmatrix)
ggmat(list(m1 = mtcars)) + geom_triangle(aes(fill = m1))

m1 <- matrix(rnorm(400, mean = 9), nrow = 20)
m2 <- matrix(rnorm(400, mean = -4), nrow = 20)
ggmat(list(m1 = m1, m2 = m2)) +
geom_triangle(aes(fill.upper = m1, fill.lower = m2)) +
scale_fill_upper_gradientn(colours = c("red", "white", "blue")) +
scale_fill_lower_gradientn(colours = c("#E9A3C9", "#F7F7F7", "#A1D76A"))

ggmat(list(m1 = mtcars), cluster.type = "all") +
geom_point(aes(size = m1))

ggmat(list(m1 = mtcars), cluster.type = "all", tree.type = "all") +
geom_tile(aes(fill = m1)) +
theme_matrix()

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