You could use the type='heatmap' with add_annotations to add the y variable. Make sure showarrow = FALSE like this:
library(plotly)
library(dplyr)
TestData1 %>%
plot_ly(x = ~Countries, y = ~variable, z = ~value, type = "heatmap", colors = c("#56B1F7", "#132B43")) %>%
add_annotations(text = ~value, x = ~Countries, y = ~variable, showarrow = FALSE, font = list(color = "white")) %>%
layout(xaxis = list(side = "top"),
yaxis = list(title = ""),
showlegend = FALSE) %>%
hide_colorbar()

Created on 2023-03-17 with reprex v2.0.2
Answer from Quinten on Stack OverflowPlotly
plotly.com โบ python โบ heatmaps
Heatmaps in Python
Arrays of rasterized values build by datashader can be visualized using plotly's heatmaps, as shown in the plotly and datashader tutorial. See function reference for px.(imshow) or https://plotly.com/python/reference/heatmap/ for more information and chart attribute options!
R Graph Gallery
r-graph-gallery.com โบ 215-interactive-heatmap-with-plotly.html
Plotly heatmap โ the R Graph Gallery
# Load the plotly package library(plotly) # Data: mtcars: data <- as.matrix(mtcars) # Normalize data data <- apply(data, 2, function(x){x/mean(x)}) # Heatmap p <- plot_ly(x=colnames(data), y=rownames(data), z = data, type = "heatmap", colorscale= "Earth", showscale = F) %>% layout(margin = list(l=120)) p # save the widget # library(htmlwidgets) # saveWidget(p, file=paste0( getwd(), "/HtmlWidget/plotlyHeatmap2.html"))
Plotly
plotly.com โบ r โบ heatmaps
Heatmaps in R
vals <- unique(scales::rescale(c(volcano))) o <- order(vals, decreasing = FALSE) cols <- scales::col_numeric("Blues", domain = NULL)(vals) colz <- setNames(data.frame(vals[o], cols[o]), NULL) fig <- plot_ly(z = volcano, colorscale = colz, type = "heatmap") fig
Kanaries
docs.kanaries.net โบ topics โบ Plotly โบ plotly-heatmap
Plotly Heatmap - Tips, Tricks, and Examples" โ Kanaries
August 17, 2023 - It's a way of plotting data that ... patterns and offer a quick visual summary of the information. Plotly heatmap is a type of heatmap that can be generated using the Plotly library in Python....
TutorialsPoint
tutorialspoint.com โบ plotly โบ plotly_heatmap.htm
Plotly - Heatmap
] harvest = np.array( [ [0.8, 2.4, 2.5, 3.9, 0.0, 4.0, 0.0], [2.4, 0.0, 4.0, 1.0, 2.7, 0.0, 0.0], [1.1, 2.4, 0.8, 4.3, 1.9, 4.4, 0.0], [0.6, 0.0, 0.3, 0.0, 3.1, 0.0, 0.0], [0.7, 1.7, 0.6, 2.6, 2.2, 6.2, 0.0], [1.3, 1.2, 0.0, 0.0, 0.0, 3.2, 5.1], [0.1, 2.0, 0.0, 1.4, 0.0, 1.9, 6.3] ] ) trace = go.Heatmap( x = vegetables, y = farmers, z = harvest, type = 'heatmap', colorscale = 'Viridis' ) data = [trace] fig = go.Figure(data = data) iplot(fig)
Plotly
plotly.com โบ python โบ density-heatmaps
Density heatmap in Python
If Plotly Express does not provide a good starting point, it is also possible to use the more generic go.Densitymap class from plotly.graph_objects. ... import pandas as pd quakes = pd.read_csv('https://raw.githubusercontent.com/plotly/datasets/master/earthquakes-23k.csv') import plotly.graph_objects as go fig = go.Figure(go.Densitymap(lat=quakes.Latitude, lon=quakes.Longitude, z=quakes.Magnitude, radius=10)) fig.update_layout(map_style="open-street-map", map_center_lon=180) fig.update_layout(margin={"r":0,"t":0,"l":0,"b":0}) fig.show()
Plotly
plotly.github.io โบ plotly.py-docs โบ generated โบ plotly.graph_objects.Heatmap.html
plotly.graph_objects.Heatmap โ 7.0.0 documentation
ytype โ If โarrayโ, the heatmapโs y coordinates are given by โyโ (the default behavior when y is provided) If โscaledโ, the heatmapโs y coordinates are given by โy0โ and โdyโ (the default behavior when y is not provided) ... zauto โ Determines whether or not the color domain is computed with respect to the input data (here in z) or the bounds set in zmin and zmax Defaults to false when zmin and zmax are set by the user. zhoverformat โ Sets the hover text formatting rule for z using d3 formatting mini-languages which are very similar to those in Python.
Educative
educative.io โบ answers โบ how-to-create-a-heatmap-plot-with-plotly-graph-objects-in-python
How to create a heatmap plot with Plotly Graph Objects in Python
Color bar: A color bar can be added to the plot to show the correspondence between colors and values. This is particularly useful when conveying the data's numeric meaning. Customization of colors: We can customize the colors used in the heatmap, including specifying the color for missing or out-of-range values.
Plotly
plotly.com โบ r โบ reference โบ heatmap
R Figure Reference: heatmap Traces
zhoverformat Parent: data[type=heatmap] Type: string Default: "" Sets the hover text formatting rulefor `z` using d3 formatting mini-languages which are very similar to those in Python.
GeeksforGeeks
geeksforgeeks.org โบ python โบ annotated-heatmaps-using-plotly-in-python
Annotated Heatmaps using Plotly in Python - GeeksforGeeks
September 5, 2020 - import plotly.figure_factory as ff import numpy as np feature_x = np.arange(0, 10, 2) feature_y = np.arange(0, 10, 3) # Creating 2-D grid of features [X, Y] = np.meshgrid(feature_x, feature_y) Z = np.cos(X / 2) + np.sin(Y / 4) fig = ff.create_annotated_heatmap(Z, colorscale='rainbow') fig.show()
Towards Data Science
towardsdatascience.com โบ home โบ latest โบ developing a timeseries heatmap in python using plotly
Developing a Timeseries Heatmap in Python Using Plotly | Towards Data Science
March 5, 2025 - While it is based on plotly.js which itself is a native Javascript binding, it has been expanded to support Python, R and other popular scripting languages. By employing a few lines of JSON in your Python script, you can easily invoke interactive visualizations including but not limited to line charts, histograms, radar plots, heatmaps and more.
Plotly
community.plotly.com โบ ๐ plotly python
Correlation Heatmap in Plotly - ๐ Plotly Python - Plotly Community Forum
March 11, 2021 - I have created a lower triangular correlation heatmap using Seaborn that I loved. Now trying to create the same using Plotly. Unfortunately, not being able to fine tune it like I did with Seaborn. names = ['U', 'V', 'W', 'X', 'Y', 'Z'] r = pd.DataFrame(index = names, columns = names) r['U'] = np.array([1.0, 0.53, 0.26, 0.63, 0.52, 0.65] ) r['V'] = np.array([0.53, 1.0, -0.17, 0.83, 1, 0.85]) r['W'] = np.array([0.26, -0.17, 1.0, 0.04, -0.15, 0.09]) r['X'] = np.array([0.63, 0.83, 0....
YouTube
youtube.com โบ watch
Heatmap - How to Create Heatmap in Plotly Python - YouTube
Learn How to create Heatmap in Plotly Python. How to create a heatmap in Python. How to Create Heatmap with Plotly library in Python.
Published: March 29, 2024
Views: 702
101workbook
datascience.101workbook.org โบ 08-visualization โบ 02-graphs โบ 02-python โบ 08-plotly-tutorial-heatmap-plot
Creating heatmap - Data Science Workbook
March 13, 2026 - DataScience Workbook / 08: Data Visualization / 2. Introduction to scientific graphing / 2.2. Plotly-Dash: interactive plotting with Python / 2.2.3. Plotly graphing - interactive examples in the JupyterLab / Creating heatmap ยท Creating dendrogram Creating clustergram RStudio โ data processing & plotting with R  Creating boxplots in R Creating heatmaps in R Creating heatmaps in R using ComplexHeatmap MODULE 09: Project Management
Codecademy
codecademy.com โบ docs โบ python:plotly โบ graph_objects โบ .heatmap()
Python:Plotly | graph_objects | .Heatmap() | Codecademy
July 24, 2024 - The .Heatmap() function in Plotly is utilized to generate heatmap visualizations, which are graphical representations of data where the individual values contained in a matrix are represented as colors.