А как насчет
library(plotly)
dat <- expand.grid(x = 1:nrow(volcano), y = 1:ncol(volcano))
dat$z <- c(volcano)
plot_ly(height = 500) %>%
layout(autosize = FALSE,
xaxis=list(title = "Hour", titlefont = list(size=20)),
yaxis=list(title = "Day", titlefont = list(size=20))) %>%
add_trace(data = dat, x = ~x, y = ~y, z = ~z, type = "heatmap",
hoverinfo = 'text',
text = ~paste("Hour:", dat$x,
"<br> Day:", dat$y,
"<br> z:", dat$z))