Add a ManifoldsBaseMakie extension

NEWS.md

@@ -5,11 +5,15 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
-## [2.3.6] unreleased
+## [2.4.0] unreleased
+
+### Added
+
+* an extension to also perform the numerical checks plots with [`Makie.jl](https://https://makie.org/) (#272).
 
 ### Fixed
 
-* (documentation of the `injectivity_radius` function now displays clearer instructions for the implementation of a radius linked to a user's own `AbstractRetractionMethod`. (#270)
+* documentation of the `injectivity_radius` function now displays clearer instructions for the implementation of a radius linked to a user's own `AbstractRetractionMethod`. (#270)
 
 ## [2.3.5] 03/04/2026
 

Project.toml

@@ -1,36 +1,41 @@
 name = "ManifoldsBase"
 uuid = "3362f125-f0bb-47a3-aa74-596ffd7ef2fb"
+version = "2.4.0"
 authors = ["Seth Axen <seth.axen@gmail.com>", "Mateusz Baran <mateuszbaran89@gmail.com>", "Ronny Bergmann <manopt@ronnybergmann.net>", "Antoine Levitt <antoine.levitt@gmail.com>"]
-version = "2.3.5"
 
 [workspace]
 projects = ["test", "docs", "tutorials"]
 
 [deps]
 LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"
 Markdown = "d6f4376e-aef5-505a-96c1-9c027394607a"
+Preferences = "21216c6a-2e73-6563-6e65-726566657250"
 Printf = "de0858da-6303-5e67-8744-51eddeeeb8d7"
 Random = "9a3f8284-a2c9-5f02-9a11-845980a1fd5c"
 
 [weakdeps]
+Makie = "ee78f7c6-11fb-53f2-987a-cfe4a2b5a57a"
 Plots = "91a5bcdd-55d7-5caf-9e0b-520d859cae80"
 Quaternions = "94ee1d12-ae83-5a48-8b1c-48b8ff168ae0"
 RecursiveArrayTools = "731186ca-8d62-57ce-b412-fbd966d074cd"
 Statistics = "10745b16-79ce-11e8-11f9-7d13ad32a3b2"
 
 [extensions]
+ManifoldsBaseMakieExt = "Makie"
 ManifoldsBasePlotsExt = "Plots"
 ManifoldsBaseQuaternionsExt = "Quaternions"
 ManifoldsBaseRecursiveArrayToolsExt = "RecursiveArrayTools"
 ManifoldsBaseStatisticsExt = "Statistics"
 
 [compat]
 LinearAlgebra = "1.6"
+Makie = "0.24"
 Markdown = "1.6"
 Plots = "1"
+Preferences = "1.4"
 Printf = "1.6"
+Quaternions = "0.7"
 Random = "1.6"
 RecursiveArrayTools = "2, 3, 4"
-Quaternions = "0.7"
 Statistics = "1.6"
 julia = "1.10"

docs/src/index.md

@@ -1,6 +1,8 @@
 # ManifoldsBase.jl
 
-`ManifoldsBase.jl` is a lightweight interface for manifolds.
+```@docs
+ManifoldsBase.ManifoldsBase
+```
 
 This packages has two main purposes.
 You can add it as a dependency if you plan to work on manifolds (generically) or if you plan to

ext/ManifoldsBaseMakieExt.jl

@@ -0,0 +1,63 @@
+module ManifoldsBaseMakieExt
+
+using ManifoldsBase
+using Makie
+using Printf: @sprintf
+import ManifoldsBase: plot_slope, plot_check_geodesic
+
+function ManifoldsBase.plot_slope(
+        ::Val{:Makie}, x, y;
+        slope = 2, line_base = 0, a = 0, b = 2.0, i = 1, j = length(x),
+    )
+    fig = Makie.Figure()
+    # Setup the log log plot
+    ax = Makie.Axis(
+        fig[1, 1];
+        xscale = log10, yscale = log10, xlabel = "t", ylabel = L"E(t)", title = "Slope plot",
+    )
+    # Main error data
+    Makie.lines!(ax, x, y; label = L"E(t)", linewidth = 3, color = :lightblue)
+    # Reference slope
+    s_line = [exp10(line_base + t * slope) for t in log10.(x)]
+    Makie.lines!(
+        ax, x, s_line; label = "slope s=$slope",
+        linestyle = :dash, color = :black, linewidth = 2
+    )
+
+    # Best-fit slope segment if i and j are provided
+    if (i != 0) && (j != 0)
+        best_line = [exp10(a + t * b) for t in log10.(x[i:j])]
+        Makie.lines!(
+            ax, x[i:j], best_line;
+            label = "best slope $(@sprintf("%.4f", b))",
+            color = :blue, linestyle = :dot, linewidth = 2,
+        )
+    end
+    Makie.axislegend(ax; position = :lt)
+    return fig
+end
+function ManifoldsBase.plot_check_geodesic(::Val{:Makie}, T, N, e_norm, e_pt, e_alpha)
+    fig = Figure()
+    ax = Axis(
+        fig[1, 1];
+        xlabel = "t", ylabel = "error magnitude", title = "Geodesic checks",
+    )
+    # Speed deviation: |‖Xᵢ‖ − mean‖X‖|
+    Makie.lines!(
+        ax, T[1:(N - 1)], e_norm;
+        label = L"|\|X_i\| - \overline{\|X\|}|", linewidth = 3, color = :lightblue
+    )
+    # Parallel-transport mismatch (norm): ‖Xᵢ − PT_{i+1→i}(X_{i+1})‖
+    lines!(
+        ax, T[1:(N - 2)], e_pt;
+        label = "PT difference (norm)", linewidth = 3, color = :blue
+    )
+    # Parallel-transport mismatch (angle): |1 − cos∠(Xᵢ, PT_{i+1→i}X_{i+1})|
+    lines!(
+        ax, T[1:(N - 2)], e_alpha;
+        label = "PT difference (angle)", linewidth = 3, color = :green
+    )
+    axislegend(ax; position = :rt)
+    return fig
+end
+end

ext/ManifoldsBasePlotsExt.jl

@@ -3,53 +3,31 @@ module ManifoldsBasePlotsExt
 using ManifoldsBase
 using Plots
 using Printf: @sprintf
-import ManifoldsBase: plot_slope
 
 function ManifoldsBase.plot_slope(
-        x,
-        y;
-        slope = 2,
-        line_base = 0,
-        a = 0,
-        b = 2.0,
-        i = 1,
-        j = length(x),
+        ::Val{:Plots}, x, y;
+        slope = 2, line_base = 0, a = 0, b = 2.0, i = 1, j = length(x),
     )
     fig = plot(
-        x,
-        y;
-        xaxis = :log,
-        yaxis = :log,
-        label = "\$E(t)\$",
-        linewidth = 3,
-        legend = :topleft,
-        color = :lightblue,
+        x, y; xaxis = :log, yaxis = :log, label = "\$E(t)\$",
+        linewidth = 3, legend = :topleft, color = :lightblue,
     )
     s_line = [exp10(line_base + t * slope) for t in log10.(x)]
     plot!(
-        fig,
-        x,
-        s_line;
-        label = "slope s=$slope",
-        linestyle = :dash,
-        color = :black,
-        linewidth = 2,
+        fig, x, s_line; label = "slope s=$slope",
+        linestyle = :dash, color = :black, linewidth = 2,
     )
     if (i != 0) && (j != 0)
         best_line = [exp10(a + t * b) for t in log10.(x[i:j])]
         plot!(
-            fig,
-            x[i:j],
-            best_line;
+            fig, x[i:j], best_line;
             label = "best slope $(@sprintf("%.4f", b))",
-            color = :blue,
-            linestyle = :dot,
-            linewidth = 2,
+            color = :blue, linestyle = :dot, linewidth = 2,
         )
     end
     return fig
 end
-function ManifoldsBase.plot_check_geodesic(T, N, e_norm, e_pt, e_alpha)
+function ManifoldsBase.plot_check_geodesic(::Val{:Plots}, T, N, e_norm, e_pt, e_alpha)
     fig = plot(
         T[1:(N - 1)], e_norm;
         # Deviation from constant speed: |‖Xᵢ‖ − mean‖X‖|

src/ManifoldsBase.jl

@@ -1,3 +1,10 @@
+@doc """
+🏔️ ManifoldsBase.jl: An interface for manifolds in Julia
+
+* 📚 Documentation: [juliamanifolds.github.io/ManifoldsBase.jl/](https://juliamanifolds.github.io/ManifoldsBase.jl/)
+* 📦 Repository: [github.com/JuliaManifolds/ManifoldsBase.jl](https://github.com/JuliaManifolds/ManifoldsBase.jl)
+* 🎯 Issues: [github.com/JuliaManifolds/ManifoldsBase.jl/issues](https://github.com/JuliaManifolds/ManifoldsBase.jl/issues)
+"""
 module ManifoldsBase
 
 import Base:
@@ -24,9 +31,11 @@ import Random: rand, rand!
 
 using LinearAlgebra
 using Markdown: @doc_str
+using Preferences
 using Printf: @sprintf
 using Random
 
+
 include("maintypes.jl")
 include("numbers.jl")
 include("Fiber.jl")
@@ -1219,6 +1228,41 @@ function zero_vector(M::AbstractManifold, p)
     zero_vector!(M, X, p)
     return X
 end
+
+#
+#
+# Internal function to set plotting backend
+
+"""
+    set_plotting_backend!(backend::String; only_fallback = false)
+
+Set the plotting backend to `backend`.
+Currently supported: `"Plots"` and `"Makie"`.
+
+An empty string resets to the default to use the last loaded one.
+"""
+function set_plotting_backend!(e::String)
+    (length(e) == 0) && (return Preferences.@delete_preferences!("PlottingBackend"))
+    # for the nonpersistent / fallback case, only set the value in the package
+    return Preferences.@set_preferences!("PlottingBackend" => e)
+end
+
+"""
+    get_plotting_backend()
+
+Return the current plotting backend.
+If none was set by the user, the last loaded one is returned. If none was loaded `nothing` is returned
+"""
+function get_plotting_backend()
+    def = nothing
+    # Choose a default – if both are loaded this order makes it Makie
+    !isnothing(Base.get_extension(ManifoldsBase, :ManifoldsBasePlotsExt)) && (def = "Plots")
+    !isnothing(Base.get_extension(ManifoldsBase, :ManifoldsBaseMakieExt)) && (def = "Makie")
+    # unless the user has set one
+    return Preferences.@load_preference("PlottingBackend", def)
+end
+
+
 include("errors.jl")
 include("parallel_transport.jl")
 include("vector_transport.jl")
@@ -1253,17 +1297,20 @@ function __init__()
     #
     return @static if isdefined(Base.Experimental, :register_error_hint) # COV_EXCL_LINE
         Base.Experimental.register_error_hint(MethodError) do io, exc, argtypes, kwargs
-            if exc.f === plot_slope
+            if (exc.f === plot_slope) || (exc.f === plot_check_geodesic)
                 print(
                     io,
                     """
 
-                    `plot_slope` has to be implemented using your favourite plotting package.
-                    A default is available when Plots.jl is added to the current environment.
+                    `$(exc.f)` has to be implemented using your favourite plotting package.
+                    A default is available when either `Plots.jl` or `Makie.jl` is loaded..
                     To then get the plotting functionality activated, do
                     """,
                 )
                 printstyled(io, "`using Plots`"; color = :cyan)
+                print(io, " or ")
+                printstyled(io, "`using CairoMakie`"; color = :cyan)
+                print(io, " or your favourite other Makie backend. You might have to add these to your environment first as well.")
             end
             if exc.f === find_best_slope_window
                 print(