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Questions tagged [heatmap]

A heat map is a graphical representation of data where the individual values contained in a matrix are represented as colors.

A heat map (or heatmap) is a graphical representation of data where the individual values contained in a matrix are represented as colors.

Heat maps can be used to display statistics (especially in statistical computing and graphics), user experience on websites.

An example of a heat map:

Source: seaborn.heatmap

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4357 questions
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One colorbar for seaborn heatmaps in subplot

Here is an example that shows a colorbar for each subplot: import seaborn as sns import matplotlib.pyplot as plt import pandas as pd import numpy as np df = pd.DataFrame(np.random.random((10,10,))) fig,axn = plt.subplots(2, 2, sharex=True,…
pbreach
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How to invert color of seaborn heatmap colorbar

I use an heatmap to visualize a confusion matrix. I like the standard colors, but I would like to have 0s in light orange and highest values in dark purple. I managed to do so only with another set of colors (light to dark violet), setting: colormap…
Fed
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What is the algorithm to create colors for a heatmap?

Assuming values are normalized from 0 to 1, what is the algoritm to get a color to create a heatmap like this? 1 is red, .5 is green, 0 is dark blue. Working in RMagick / ImageMagick.
B Seven
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Recording user data for heatmap with JavaScript

I was wondering how sites such as crazyegg.com store user click data during a session. Obviously there is some underlying script which is storing each clicks data, but how is that data then populated into a database? It seems to me the simple…
Hanpan
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How to understand Seaborn's heatmap annotation format

I am looking for a way to show "0.0045" as "0.45%" on seaboarn's heatmap by specifying the fmt keyword: sns.heatmap(data, annot=True, fmt='??') However, I did not find a list of format to use. Searching between different examples, I have seen "d",…
Lisa
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display a matrix, including the values, as a heatmap

What I'd like to do is take this matrix: > partb 0.5 1.5 1a 1b -2 -3 A1FCLYRBAB430F 0.26 0.00 0.74 0.00 0.00 0.00 A1SO604B523Q68 0.67 0.33 0.00 0.00 0.00 0.00 A386SQL39RBV7G 0.00 0.33 0.33 0.33 0.00 0.00 A3GTXOXRSE74WD 0.41…
Nathan VanHoudnos
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How to recalculate x,y coordinates based on screensize

I'm have a heat map application and store I store the x,y coordinates of a click and also the viewport width and height. Real data for 2 clicks: x, y, width, height 433, 343, 1257, 959 331, 823, 1257, 959 The issue is when I resize the screen…
Naterade
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Moving color key in R heatmap.2 (function of gplots package)

I read the heatmap.2 help manual a couple of times now, and also in various online tutorials I didn't read about a way to move the color key to a different position. Now, I am wondering if it is even possible? The color key is in the upper left…
user2015601
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Circular Heatmap that looks like a donut

I'm trying to create circular heatmap with ggplot2 so I can use a larger number of labels around the circumference of a circle. I'd like to have it look more like a donut with an empty hole in the middle but at the same time not losing any rows…
user1905004
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ggplot2 heatmap with colors for ranged values

I want to make a heatmap in ggplot2. My toy data and code is: set.seed(12345) dat <- data.frame( Row = rep(x = LETTERS[1:5], times = 10) , Col = rep(x = LETTERS[1:10], each = 5) , Y = rnorm(n = 50, mean = 0, sd = 1) …
MYaseen208
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Custom Annotation Seaborn Heatmap

I'm using Seaborn in Python to create a Heatmap. I'm able to annotate the cells with the values passed in, but I'd like to add annotations that signify what the cell means. For example, instead of merely seeing 0.000000, I'd like to see the…
TayTay
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Calculate RGB value for a range of values to create heat map

I am trying to create a heat map with python. For this I have to assign an RGB value to every value in the range of possible values. I thought of changing the color from blue (minimal value) over green to red (maximal value). The picture example…
aldorado
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Correlation among multiple categorical variables

I have a data set made of 22 categorical variables (non-ordered). I would like to visualize their correlation in a nice heatmap. Since the Pandas built-in function DataFrame.corr(method='pearson', min_periods=1) only implement correlation…
zar3bski
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Diagonal labels orientation on x-axis in heatmap(s)

Creating heatmaps in R has been a topic of many posts, discussions and iterations. My main problem is that it's tricky to combine visual flexibility of solutions available in lattice levelplot() or basic graphics image(), with effortless clustering…
Geek On Acid
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differences in heatmap/clustering defaults in R (heatplot versus heatmap.2)?

I'm comparing two ways of creating heatmaps with dendrograms in R, one with made4's heatplot and one with gplots of heatmap.2. The appropriate results depend on the analysis but I'm trying to understand why the defaults are so different, and how to…
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