Ask Your Question
0

How can you create a ggplot2 heatmap that has a vector for the heatmap located at the bottom and a vector for the values located on the side?

asked 2022-02-26 11:00:00 +0000

woof gravatar image

edit retag flag offensive close merge delete

1 Answer

Sort by ยป oldest newest most voted
1

answered 2022-05-17 19:00:00 +0000

plato gravatar image

To create a ggplot2 heatmap that has a vector for the heatmap located at the bottom and a vector for the values located on the side, you can use the ggheatmap() function from the ggpubr package.

Here is an example code:

library(ggpubr) library(dplyr) # creating a matrix with random values set.seed(123) mat <- matrix(sample(1:50, 15), ncol = 3, nrow = 5) # creating a data.frame with the row and column indices df <- expand.grid(row = 1:nrow(mat), col = 1:ncol(mat)) df$value <- as.vector(mat) # creating the heatmap ggheatmap(df, x = "col", y = "row", color = "value", ylim = c(0.5, nrow(mat) + 0.5), xlab = "Column", ylab = "Row", font.label = list(size = 12, color = "black"), font.main = list(size = 14, color = "black"), legend.title = "Value", legend.label.size = 12, heatmap_width = unit(5, "cm"), heatmap_height = unit(5, "cm")) + theme(axis.text.x = element_text(angle = 90, hjust = 1, vjust = 0.5)) + annotate("text", x = seq_along(mat), y = rep(0.3, ncol(mat)), label = seq_along(mat), color = "black", fontface = "bold") + annotate("text", x = rep(0.3, nrow(mat)), y = seq_along(mat), label = LETTERS[1:nrow(mat)], color = "black", fontface = "bold") + scale_fill_gradient(low = "white", high = "blue") + guides(fill = guide_colorbar(title.position = "top", title.vjust = 1, label.position = "top", label.vjust = 0.5, nbin = 10)) 

In this code, we first create a matrix mat with random values. We then convert it into a data frame df with the row and column indices and the corresponding values.

We then use the ggheatmap() function with the color argument set to "value" to create the heatmap. We also set the x and y arguments to "col" and "row", respectively, to indicate the column and row indices in the data frame.

To create the vectors for the heatmap and values, we use the annotate() function to add text labels to the plot. We also rotate the x-axis labels by 90 degrees using the theme() function.

Finally, we use the scale_fill_gradient() function and the guides() function to set the color scale and the color bar legend, respectively.

edit flag offensive delete link more

Your Answer

Please start posting anonymously - your entry will be published after you log in or create a new account. This space is reserved only for answers. If you would like to engage in a discussion, please instead post a comment under the question or an answer that you would like to discuss

Add Answer


Question Tools

Stats

Asked: 2022-02-26 11:00:00 +0000

Seen: 13 times

Last updated: May 17 '22