Combine pheatmap

Talk is cheap, this is code:

library(grid)
library(gridExtra)
library(pheatmap)
library(ggplot2)
library(colormap)
items=names(colormaps)
plot_list=list()
for (a in items[1:8]){
  x= pheatmap(volcano,
              cluster_rows = F,
              cluster_cols = F,
              main = a,
              height = 3,
              width = 3,
              border_color = NA,
              color = colormap_pal(colormap = colormaps[[a]])(100),silent = T)
  plot_list[[a]] = x[[4]]     ##to save each plot into a list. note the [[4]]
}

cowplot::plot_grid(plotlist = plot_list[1:8],ncol = 2,nrow = 4)

test equation: ;