How do I limit the range of the viridis colour scale?

Question

I have two sets of data, which I want to present using a heat map with the viridis color scale. For the first data set, my values range from 0 to 1.2 and I can easily see the differences I want to see. However my second data set has some outliers, resulting in a range from 0 to 2. Now it's harder to see the differences in the interesting range between 0 and 1 and it's more diffucult to compare the two images directly. Is there a possibility to show the data from 0 to 1.2 using the viridis colour scale while showing the higher values in yellow ("highest" colour of the viridis scale)? Here is an example:

library(viridis)

#Create Data
DataSet1 <- expand.grid(x = 0:5, y = 0:5)
DataSet1$z <- runif(36, 0, 1.2)

DataSet2 <- expand.grid(x = 0:5, y = 0:5)
DataSet2$z <- runif(36, 0, 2)

#Plot Data
ggplot(DataSet1, aes(x, y, fill = z)) + 
  geom_tile() +
  scale_fill_viridis() +
  geom_text(aes(label = round(z, 2)), size = 2)

DataSet1: Differences between 0.5 and 0.7 are easy to see

ggplot(DataSet2, aes(x, y, fill = z)) + 
  geom_tile() +
  scale_fill_viridis() +
  geom_text(aes(label = round(z, 2)), size = 2)

DataSet2: Differences between 0.5 and 0.7 are diffucult to see

Answer 1

Are you looking for something like this?

ggplot(DataSet2, aes(x, y, fill = z)) + 
  geom_tile() +
  scale_fill_gradient(low="green", high="red", limits=c(0, 1.2), 
                      na.value = "yellow") +
  geom_text(aes(label = round(z, 2)), size = 2)

Using the viridis colors, asper jazzurro recommendation.

ggplot(DataSet2, aes(x, y, fill = z)) + 
  geom_tile() + 
  scale_fill_gradientn(colors = viridis_pal()(9), limits=c(0, 1.2), 
                       na.value = "#FDE725FF") + 
  geom_text(aes(label = round(z, 2)), size = 2)