extension:.md

format_name:markdown

format_version:'1.1'

jupytext_version:1.1.1

jupytext_version:1.2.1

kernelspec:

display_name:Python 3

language:python

name:python

nbconvert_exporter:python

pygments_lexer:ipython3

version:3.6.8

version:3.7.3

plotly:

description:How to set colorscales and heatmap colorscales in Python and Plotly.

name:Colorscales

order:22

permalink:python/colorscales/

thumbnail:thumbnail/heatmap_colorscale.jpg

redirect_from:python/logarithmic-color-scale/

thumbnail:thumbnail/heatmap_colorscale.jpg

v4upgrade:true

fig.show()

The following example uses[cmid](https://plot.ly/python/reference/#scatter-marker-cmid) attribute to set the mid-point of the color domain by scaling[cmin](https://plot.ly/python/reference/#scatter-marker-cmin) and/or[cmax](https://plot.ly/python/reference/#scatter-marker-cmax) to be equidistant to this point. It only has impact when[marker.line.color](https://plot.ly/python/reference/#scattercarpet-marker-line-color) sets to a numerical array, and[marker.line.cauto](https://plot.ly/python/reference/#scattercarpet-marker-line-cauto) is`True`. The heatmap chart uses[zmid](https://plot.ly/python/reference/#heatmap-zmid) attribute to set the mid-point of the color domain by scaling[zmin](https://plot.ly/python/reference/#heatmap-zmin) and/or[zmax](https://plot.ly/python/reference/#heatmap-zmax) to be equidistant to this point.

import plotly.graph_objectsas go

fig= go.Figure()

fig.add_trace(go.Scatter(

y=[1,2,0,1],

mode="markers",

marker={

"size":25,

"color": [1,4,8],

"cmid":0,

"colorbar": {

"len":0.5,

"y":1,

"yanchor":"top",

"title": {"text":"cmid=0","side":"right"}

}}))

fig.add_trace(go.Heatmap(

z=[[1,5,3,2], [5,3,7,9], [3,2,6,4]],

zmid=10,

colorbar={

"len":0.5,

"y":0.5,

"yanchor":"top",

"title": {"text":"zmid=10","side":"right"}

}))

fig.show()

[1.,'rgb(0, 0, 0)'],#100000

],

colorbar=dict(

colorbar=dict(

tick0=0,

tickmode='array',

tickvals= [0,1000,10000,100000]