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Heatmaps in F#

How to make Heatmaps in F# with Plotly.


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In [1]:
#r "nuget: Plotly.NET, 2.0.0-preview.8" #r "nuget: Plotly.NET.Interactive, 2.0.0-preview.8" #r "nuget: Deedle" #r "nuget: FSharp.Data"
Installed Packages
  • Deedle, 2.4.3
  • FSharp.Data, 4.2.4
  • Plotly.NET, 2.0.0-preview.8
  • Plotly.NET.Interactive, 2.0.0-preview.8

Loading extensions from Plotly.NET.Interactive.dll

Added Kernel Extension including formatters for Plotly.NET charts.

Basic Heatmap

In [2]:
open Plotly.NET let matrix = [[1.;1.5;0.7;2.7]; [2.;0.5;1.2;1.4]; [0.1;2.6;2.4;3.0];] let rownames = ["p3";"p2";"p1"] let colnames = ["Tp0";"Tp30";"Tp60";"Tp160"] let colorscaleValue = StyleParam.Colorscale.Custom [(0.0,"#3D9970");(1.0,"#001f3f")] Chart.Heatmap( data=matrix,ColNames=colnames,RowNames=rownames, Colorscale=colorscaleValue, Showscale=true ) |> Chart.withSize(700.,500.) |> Chart.withMarginSize(Left=200.)
Out[2]:
In [3]:
open Deedle open FSharp.Data let volcano = Http.RequestString "https://raw.githubusercontent.com/plotly/datasets/master/volcano.csv" |> fun csv -> Frame.ReadCsvString(csv,true,separators=",") Chart.Heatmap(data=Frame.toJaggedArray(volcano))
Out[3]:

Sequential Colorscales: Greys

In [4]:
open Deedle open FSharp.Data let volcano = Http.RequestString "https://raw.githubusercontent.com/plotly/datasets/master/volcano.csv" |> fun csv -> Frame.ReadCsvString(csv,true,separators=",") Chart.Heatmap(data=Frame.toJaggedArray(volcano),Colorscale=StyleParam.Colorscale.Greys)
Out[4]:

Custom colorscales

In [5]:
open Deedle open FSharp.Data let volcano = Http.RequestString "https://raw.githubusercontent.com/plotly/datasets/master/volcano.csv" |> fun csv -> Frame.ReadCsvString(csv,true,separators=",") let customColorscale = StyleParam.Colorscale.Custom [(0.0,"red");(1.0,"green")] Chart.Heatmap(data=Frame.toJaggedArray(volcano),Colorscale=customColorscale)
Out[5]: