Heatmap in R (3 Examples) | Base R, ggplot2 & plotly Package | How to Create Heatmaps

R code of this video:

##### Example data
data ＜- matrix(rnorm(100, 0, 10), nrow = 10, ncol = 10) # Create example data
colnames(data) ＜- paste0("col", 1:10) # Column names
rownames(data) ＜- paste0("row", 1:10) # Row names

##### Example 1
heatmap(data) # Apply heatmap function

##### Example 2
heatmap(data, Rowv = NA, Colv = NA) # Remove dendogram

##### Example 3
my_colors ＜- colorRampPalette(c("cyan", "deeppink3")) # Manual color range
heatmap(data, col = my_colors(100)) # Heatmap with manual colors

##### Example 4
library("reshape") # Load reshape package

data_melt ＜- melt(data) # Reorder data

library("ggplot2") # Load ggplot2 package

ggp ＜- ggplot(data_melt, aes(X1, X2)) + # Create heatmap with ggplot2
geom_tile(aes(fill = value))
ggp # Print heatmap

##### Example 5
ggp + scale_fill_gradient(low = "green", high = "black") # Manual colors of heatmap

##### Example 6
library("plotly") # Load plotly package

plot_ly(z = data, type = "heatmap") # Apply plot_ly function

##### Example 7
plot_ly(z = data, colorscale = "Greys", type = "heatmap") # Manual colors

[RUJedi]

Thanks for the great walk-through! Many other videos go through so many unnecessary steps, but you kept it concise and still hit so many comparative points!

[einandaraung]

Thank you for details explaining. I have known many kind of heatmap code.

[meseretmuche]

really thank you for providing us remakable video

[elizabeth]

This was very useful. thank you so much :)

[rajaranidreamhome]

I did all the steps and finally the viewer doesn't shows the plot_ly heat map... What should I do... And also I wanted to change the direction and overlapping x1 axis value for that what I have to do

[YummiestOrphan]

Hi,

How can I use the row names from my file on the heatmap, currently it just says Row 1 all the way to Row 6 rather than the actual title?

heatmap(as.matrix(my data[, -1]))

This is the script I'm using, its the only way I could get it to work as its not a matrix apparently. Thank you

[RjAtifAyub]

If we copy your script and apply on our original data not on the save data by R then it's gives numeric error. Please tell me how to resolve numeric error issues. Thanks in anticipation.💐

[Apsaalooke]

Thank you for all your videos. They're all very useful. Can you explain, please, how to make a spectral analysis by R in one of your videos? Periodogram or something else. Or maybe you've already done it...

[samemery]

What if you wanted more colors than 100 in example 3, how would you do that?

[infotainment]

Great explanation. I have two groups (A and B). How can I get a heat map? For example, data<- data.frame(groups=c("A", "A", "A", "B", "B", "B"), E1= c(2, 3, 4, 5, 6, 7), E2= c(3, 5, 6, 8, 9, 7) ).

[muhammadusmanali]

How to creat heat map analysis when i have more then 2 data (i mean to say i have 2 experiment data and i want to creat both data show in one heat map Graph )

[shandrymmasetshaba]

Thank you for a detailed tutorial!!
I have a question, what are the codes for inserting colour key on the heatmap?

[hugooliveira]

Great video!!! But when i do create some heatmap using ggplot2, how can i set the values? (in your video for example, the heatmap values were setted as -20 to +20). Thanks!!

[lihe]

thank you for the tutorial! but how can I create a heatmap with more than 2 colors using the ggplot2 package?

[hr_foods]

I want to change color for each columns how I do, because for some column I need positive value or some negative

[ankitkachchhi]

Have made heatmap successfully except I have 68 labels in data instead I am getting only 34 row labels in the heatmap. Heatmap is perfect but this number of row labels are half