Add Chart.Residual – Modified Lollipop Chart Implementation

Plotly.NET.sln

@@ -140,6 +140,7 @@ Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "04_distribution-charts", "0
 		docs\distribution-charts\point-density.fsx = docs\distribution-charts\point-density.fsx
 		docs\distribution-charts\splom.fsx = docs\distribution-charts\splom.fsx
 		docs\distribution-charts\violin-plots.fsx = docs\distribution-charts\violin-plots.fsx
+		docs\distribution-charts\residual.fsx = docs\distribution-charts\residual.fsx
 	EndProjectSection
 EndProject
 Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "01_chart-layout", "01_chart-layout", "{C7D0EF67-9A18-49DD-AC79-944E384BD8D0}"

docs/distribution-charts/residual.fsx

@@ -0,0 +1,74 @@
+(**
+---
+title: Residual chart
+category: Distribution Charts
+categoryindex: 5
+index: 10
+---
+*)
+
+(*** hide ***)
+
+(*** condition: prepare ***)
+#r "nuget: Newtonsoft.JSON, 13.0.3"
+#r "nuget: DynamicObj, 7.0.1"
+#r "nuget: Giraffe.ViewEngine.StrongName, 2.0.0-alpha1"
+#r "../../src/Plotly.NET/bin/Release/netstandard2.0/Plotly.NET.dll"
+
+Plotly.NET.Defaults.DefaultDisplayOptions <-
+    Plotly.NET.DisplayOptions.init (PlotlyJSReference = Plotly.NET.PlotlyJSReference.NoReference)
+
+(*** condition: ipynb ***)
+#if IPYNB
+#r "nuget: Plotly.NET, {{fsdocs-package-version}}"
+#r "nuget: Plotly.NET.Interactive, {{fsdocs-package-version}}"
+#endif // IPYNB
+
+(** 
+# Residual chart
+
+[![Binder]({{root}}img/badge-binder.svg)](https://mybinder.org/v2/gh/plotly/plotly.net/gh-pages?urlpath=/tree/home/jovyan/{{fsdocs-source-basename}}.ipynb)&emsp;
+[![Notebook]({{root}}img/badge-notebook.svg)]({{root}}{{fsdocs-source-basename}}.ipynb)
+
+*Summary:* This example shows how to create a Residual (or Lollipop) chart in F#.
+
+Let's first create some data for the purpose of creating example charts:
+
+*)
+
+open Plotly.NET
+
+let ydata =
+    [9.;25.;-73.;-30.;3.;35.;-35.;9.;-3.;33.;17.;25.;-15.;38.;-2.;36.;29.;-23.;15.;19]
+let mean = Seq.average ydata
+
+let xy = Seq.indexed ydata
+
+(**
+## What is a Residual (Lollipop) Chart?
+
+A Residual or Lollipop chart is a type of chart that showcases the deviation of values to a reference value, often the **mean**, **median**, or a custom threshold.
+
+- Each observation is represented by a **dot** connected to the reference line by a **line segment**.
+- This type of visualization is useful for identifying **patterns**, **outliers**, or **distribution skewness** in relation to a central value.
+- This approach is also helpful when visualizing residuals in regression models to assess **SSR (Sum of Squared Residuals)**, or highlight deviations to measures like **R²**.
+*)
+
+let residualChart = 
+    Chart.Residual(
+        xy=xy,
+        referenceValue = mean,
+        MarkerColor = Color.fromString "purple",
+        LineColor = Color.fromString "blue",
+        ReferenceColor = Color.fromString "black"
+    )
+
+(*** condition: ipynb ***)
+#if IPYNB
+residualChart
+#endif // IPYNB
+
+(***hide***)
+residualChart |> GenericChart.toChartHTML
+(***include-it-raw***)
+