diff -r 6105b5cd8d89 -r f0e8704d3f0e src/plot.rs
--- a/src/plot.rs	Tue Aug 01 10:25:09 2023 +0300
+++ b/src/plot.rs	Mon Feb 17 13:54:53 2025 -0500
@@ -1,29 +1,14 @@
 //! Plotting helper utilities
 
 use numeric_literals::replace_float_literals;
-use std::io::Write;
-use image::{
-    ImageFormat,
-    ImageBuffer,
-    Rgb
-};
-use itertools::izip;
-use colorbrewer::Palette as CbPalette;
-
+use serde::Serialize;
 use alg_tools::types::*;
 use alg_tools::lingrid::LinGrid;
 use alg_tools::mapping::RealMapping;
 use alg_tools::loc::Loc;
-use alg_tools::bisection_tree::Bounds;
-use alg_tools::maputil::map4;
 use alg_tools::tabledump::write_csv;
 use crate::measures::*;
 
-/// Default RGB ramp from [`colorbrewer`].
-///
-/// This is a tuple of parameters to [`colorbrewer::get_color_ramp`].
-const RAMP : (CbPalette, u32) = (CbPalette::RdBu, 11);
-
 /// Helper trait for implementing dimension-dependent plotting routines.
 pub trait Plotting<const N : usize> {
     /// Plot several mappings and a discrete measure into a file.
@@ -32,13 +17,10 @@
         T1 : RealMapping<F, N>,
         T2 : RealMapping<F, N>
     > (
-        g_explanation : String,
-        g : &T1,
-        ω_explanation : String,
+        g : Option<&T1>,
         ω : Option<&T2>,
         grid : LinGrid<F, N>,
-        bnd : Option<Bounds<F>>,
-        μ : &DiscreteMeasure<Loc<F, N>, F>,
+        μ : &RNDM<F, N>,
         filename : String,
     );
 
@@ -50,78 +32,57 @@
         g : &T1,
         grid : LinGrid<F, N>,
         filename : String,
-        explanation : String
     );
 }
 
 /// Helper type for looking up a [`Plotting`] based on dimension.
 pub struct PlotLookup;
 
+#[derive(Serialize)]
+struct CSVHelper1<F : Float> {
+    x : F,
+    f : F,
+}
+
+#[derive(Serialize)]
+struct CSVHelper1_2<F : Float>{
+    x : F,
+    g : Option<F>,
+    omega : Option<F>
+}
+
+#[derive(Serialize)]
+struct CSVSpike1<F : Float> {
+    x : F,
+    alpha : F,
+}
+
 impl Plotting<1> for PlotLookup {
     fn plot_into_file_spikes<
         F : Float,
         T1 : RealMapping<F, 1>,
         T2 : RealMapping<F, 1>
     > (
-        g_explanation : String,
-        g : &T1,
-        ω_explanation : String,
+        g0 : Option<&T1>,
         ω0 : Option<&T2>,
         grid : LinGrid<F, 1>,
-        bnd0 : Option<Bounds<F>>,
         μ : &DiscreteMeasure<Loc<F, 1>, F>,
         filename : String,
     ) {
-        let start = grid.start[0].as_();
-        let end = grid.end[0].as_();
-        let m = μ.iter_masses().fold(F::ZERO, |m, α| m.max(α));
-        let s = μ.iter_masses().fold(F::ZERO, |m, α| m.add(α));
-        let mut spike_scale = F::ONE;
-
-        let mut plotter = poloto::plot(
-            "f", "x",
-            format!("f(x); spike max={:.4}, n={}, ∑={:.4}", m, μ.len(), s)
-        ).move_into();
-
-        if let Some(ω) = ω0 {
-            let graph_ω = grid.into_iter().map(|x@Loc([x0]) : Loc<F, 1>| {
-                [x0.as_(), ω.apply(&x).as_()]
-            });
-            plotter.line(ω_explanation.as_str(), graph_ω.clone());
-            // let csv_f = format!("{}.txt", filename);
-            // write_csv(graph_ω, csv_f).expect("CSV save error");
-        }
-
-        let graph_g = grid.into_iter().map(|x@Loc([x0]) : Loc<F, 1>| {
-            [x0.as_(), g.apply(&x).as_()]
+        let data = grid.into_iter().map(|p@Loc([x]) : Loc<F, 1>| CSVHelper1_2 {
+            x,
+            g : g0.map(|g| g.apply(&p)),
+            omega : ω0.map(|ω| ω.apply(&p))
         });
-        plotter.line(g_explanation.as_str(), graph_g.clone());
-        // let csv_f = format!("{}.txt", filename);
-        // write_csv(graph_g, csv_f).expect("CSV save error");
-
-        bnd0.map(|bnd| {
-            let upperb = bnd.upper().as_();
-            let lowerb =  bnd.lower().as_();
-            let upper : [[f64; 2]; 2] = [[start, upperb], [end, upperb]];
-            let lower = [[start, lowerb], [end, lowerb]];
-            spike_scale *= bnd.upper();
+        let csv_f = format!("{}_functions.csv", filename);
+        write_csv(data, csv_f).expect("CSV save error");
 
-            plotter.line("upper bound", upper)
-                   .line("lower bound", lower)
-                   .ymarker(lowerb)
-                   .ymarker(upperb);
+        let spikes = μ.iter_spikes().map(|δ| {
+            let Loc([x]) = δ.x;
+            CSVSpike1 { x, alpha : δ.α }
         });
-
-        for &DeltaMeasure{ α, x : Loc([x]) } in μ.iter_spikes() {
-            let spike = [[x.as_(), 0.0], [x.as_(), (α/m * spike_scale).as_()]];
-            plotter.line("", spike);
-        }
-
-        let svg = format!("{}", poloto::disp(|a| poloto::simple_theme(a, plotter)));
-
-        std::fs::File::create(filename + ".svg").and_then(|mut file|
-            file.write_all(svg.as_bytes())
-        ).expect("SVG save error");
+        let csv_f = format!("{}_spikes.csv", filename);
+        write_csv(spikes, csv_f).expect("CSV save error");
     }
 
     fn plot_into_file<
@@ -131,150 +92,37 @@
         g : &T1,
         grid : LinGrid<F, 1>,
         filename : String,
-        explanation : String
     ) {
-        let graph_g = grid.into_iter().map(|x@Loc([x0]) : Loc<F, 1>| {
-            [x0.as_(), g.apply(&x).as_()]
+        let data = grid.into_iter().map(|p@Loc([x]) : Loc<F, 1>| CSVHelper1 {
+            x,
+            f : g.apply(&p),
         });
-
-        let plotter: poloto::Plotter<'_, float, float> = poloto::plot("f", "x", "f(x)")
-            .line(explanation.as_str(), graph_g.clone())
-            .move_into();
-
-        let svg = format!("{}", poloto::disp(|a| poloto::simple_theme(a, plotter)));
-
-        let svg_f = format!("{}.svg", filename);
-        std::fs::File::create(svg_f).and_then(|mut file|
-            file.write_all(svg.as_bytes())
-        ).expect("SVG save error");
-
         let csv_f = format!("{}.txt", filename);
-        write_csv(graph_g, csv_f).expect("CSV save error");
+        write_csv(data, csv_f).expect("CSV save error");
     }
 
 }
 
-/// Convert $[0, 1] ∈ F$ to $\\\{0, …, M\\\} ∈ F$ where $M=$`F::RANGE_MAX`.
-#[inline]
-fn scale_uint<F, U>(v : F) -> U
-where F : Float + CastFrom<U> + num_traits::cast::AsPrimitive<U>,
-      U : Unsigned {
-    (v*F::cast_from(U::RANGE_MAX)).as_()
-}
-
-/// Convert $[a, b] ∈ F$ to $\\\{0, …, M\\\} ∈ F$ where $M=$`F::RANGE_MAX`.
-#[replace_float_literals(F::cast_from(literal))]
-#[inline]
-fn scale_range_uint<F, U>(v : F, &Bounds(a, b) : &Bounds<F>) -> U
-where F : Float + CastFrom<U> + num_traits::cast::AsPrimitive<U>,
-      U : Unsigned {
-    debug_assert!(a < b);
-    scale_uint(((v - a)/(b - a)).max(0.0).min(1.0))
-}
-
-
-/// Sample a mapping on a grid.
-///
-/// Returns a vector of values as well as upper and lower bounds of the values.
-fn rawdata_and_range<F, T>(grid : &LinGrid<F, 2>, g :&T) -> (Vec<F>, Bounds<F>)
-where F : Float,
-      T : RealMapping<F, 2> {
-    let rawdata : Vec<F> = grid.into_iter().map(|x| g.apply(&x)).collect();
-    let range = rawdata.iter()
-                        .map(|&v| Bounds(v, v))
-                        .reduce(|b1, b2| b1.common(&b2))
-                        .unwrap();
-    (rawdata, range)
+#[derive(Serialize)]
+struct CSVHelper2<F : Float> {
+    x : F,
+    y : F,
+    f : F,
 }
 
-/*fn to_range<'a, F, U>(rawdata : &'a Vec<F>,  range : &'a Bounds<F>)
--> std::iter::Map<std::slice::Iter<'a, F>, impl FnMut(&'a F) -> U>
-where F : Float + CastFrom<U> + num_traits::cast::AsPrimitive<U>,
-      U : Unsigned {
-    rawdata.iter().map(move |&v| scale_range_uint(v, range))
-}*/
-
-/// Convert a scalar value to an RGB triplet.
-///
-/// Converts the value `v` supposed to be within the range `[a, b]` to an rgb value according
-/// to the given `ramp` of equally-spaced rgb interpolation points.
-#[replace_float_literals(F::cast_from(literal))]
-fn one_to_ramp<F, U>(
-    &Bounds(a, b) : &Bounds<F>,
-    ramp : &Vec<Loc<F, 3>>,
-    v : F,
-) -> Rgb<U>
-where F : Float + CastFrom<U> + num_traits::cast::AsPrimitive<U>,
-      U : Unsigned {
-
-    let n = ramp.len() - 1;
-    let m = F::cast_from(U::RANGE_MAX);
-    let ramprange = move |v : F| {let m : usize = v.as_(); m.min(n).max(0) };
-
-    let w = F::cast_from(n) * (v - a) / (b - a);  // convert [0, 1] to [0, n]
-    let (l, u) = (w.floor(), w.ceil());           // Find closest integers
-    let (rl, ru) = (ramprange(l), ramprange(u));
-    let (cl, cu) = (ramp[rl], ramp[ru]);          // Get corresponding colours
-    let λ = match rl==ru {                        // Interpolation factor
-        true => 0.0,
-        false => (u - w) / (u - l),
-    };
-    let Loc(rgb) = cl * λ + cu * (1.0 - λ);       // Interpolate
-
-    Rgb(rgb.map(|v| (v * m).round().min(m).max(0.0).as_()))
+#[derive(Serialize)]
+struct CSVHelper2_2<F : Float>{
+    x : F,
+    y : F,
+    g : Option<F>,
+    omega : Option<F>
 }
 
-/// Convert a an iterator over scalar values to an iterator over RGB triplets.
-///
-/// The conversion is that performed by [`one_to_ramp`].
-#[replace_float_literals(F::cast_from(literal))]
-fn to_ramp<'a, F, U, I>(
-    bounds : &'a Bounds<F>,
-    ramp : &'a Vec<Loc<F, 3>>,
-    iter : I,
-) -> std::iter::Map<I, impl FnMut(F) -> Rgb<U> + 'a>
-where F : Float + CastFrom<U> + num_traits::cast::AsPrimitive<U>,
-      U : Unsigned,
-      I : Iterator<Item = F> + 'a {
-    iter.map(move |v| one_to_ramp(bounds, ramp, v))
-}
-
-/// Convert a [`colorbrewer`] sepcification to a ramp of rgb triplets.
-fn get_ramp<F : Float>((palette, nb) : (CbPalette, u32)) -> Vec<Loc<F, 3>> {
-    let m = F::cast_from(u8::MAX);
-    colorbrewer::get_color_ramp(palette, nb)
-                 .expect("Invalid colorbrewer ramp")
-                 .into_iter()
-                 .map(|rgb::RGB{r, g, b}| {
-                    [r, g, b].map(|c| F::cast_from(c) / m).into()
-                 }).collect()
-}
-
-/// Perform hue shifting of an RGB value.
-///
-// The hue `ω` is in radians.
-#[replace_float_literals(F::cast_from(literal))]
-fn hueshift<F, U>(ω : F, Rgb([r_in, g_in, b_in]) : Rgb<U>) -> Rgb<U>
-where F : Float + CastFrom<U>,
-      U : Unsigned {
-    let m = F::cast_from(U::RANGE_MAX);
-    let r = F::cast_from(r_in) / m;
-    let g = F::cast_from(g_in) / m;
-    let b = F::cast_from(b_in) / m;
-    let u = ω.cos();
-    let w = ω.sin();
-
-    let nr = (0.299 + 0.701*u + 0.168*w) * r
-              + (0.587 - 0.587*u + 0.330*w) * g
-              + (0.114 - 0.114*u - 0.497*w) * b;
-    let ng = (0.299 - 0.299*u - 0.328*w) * r
-              + (0.587 + 0.413*u + 0.035*w) * g
-              + (0.114 - 0.114*u + 0.292*w) *b;
-    let nb = (0.299 - 0.3*u + 1.25*w) * r
-              + (0.587 - 0.588*u - 1.05*w) * g
-              + (0.114 + 0.886*u - 0.203*w) * b;
-
-    Rgb([nr, ng, nb].map(scale_uint))
+#[derive(Serialize)]
+struct CSVSpike2<F : Float> {
+    x : F,
+    y : F,
+    alpha : F,
 }
 
 
@@ -285,55 +133,27 @@
         T1 : RealMapping<F, 2>,
         T2 : RealMapping<F, 2>
     > (
-        _g_explanation : String,
-        g : &T1,
-        _ω_explanation : String,
+        g0 : Option<&T1>,
         ω0 : Option<&T2>,
         grid : LinGrid<F, 2>,
-        _bnd0 : Option<Bounds<F>>,
         μ : &DiscreteMeasure<Loc<F, 2>, F>,
         filename : String,
     ) {
-        let [w, h] = grid.count;
-        let (rawdata_g, range_g) = rawdata_and_range(&grid, g);
-        let (rawdata_ω, range) = match ω0 {
-            Some(ω) => {
-                let (rawdata_ω, range_ω) = rawdata_and_range(&grid, ω);
-                (rawdata_ω, range_g.common(&range_ω))
-            },
-            None => {
-                let mut zeros = Vec::new();
-                zeros.resize(rawdata_g.len(), 0.0);
-                (zeros, range_g)
-            }
-        };
-        let ramp = get_ramp(RAMP);
-        let base_im_iter = to_ramp::<F, u16, _>(&range_g, &ramp, rawdata_g.iter().cloned());
-        let im_iter = izip!(base_im_iter, rawdata_g.iter(), rawdata_ω.iter())
-            .map(|(rgb, &v, &w)| {
-                hueshift(2.0 * F::PI * (v - w).abs() / range.upper(), rgb)
-            });
-        let mut img = ImageBuffer::new(w as u32, h as u32);
-        img.pixels_mut()
-           .zip(im_iter)
-           .for_each(|(p, v)| *p = v);
+        let data = grid.into_iter().map(|p@Loc([x, y]) : Loc<F, 2>| CSVHelper2_2 {
+            x,
+            y,
+            g : g0.map(|g| g.apply(&p)),
+            omega : ω0.map(|ω| ω.apply(&p))
+        });
+        let csv_f = format!("{}_functions.csv", filename);
+        write_csv(data, csv_f).expect("CSV save error");
 
-        // Add spikes
-        let m = μ.iter_masses().fold(F::ZERO, |m, α| m.max(α));
-        let μ_range = Bounds(F::ZERO, m);
-        for &DeltaMeasure{ ref x, α } in μ.iter_spikes() {
-            let [a, b] = map4(x, &grid.start, &grid.end, &grid.count, |&ξ, &a, &b, &n| {
-                ((ξ-a)/(b-a)*F::cast_from(n)).as_()
-            });
-            if a < w.as_() && b < h.as_() {
-                let sc : u16 = scale_range_uint(α, &μ_range);
-                // TODO: use max of points that map to this pixel.
-                img[(a, b)] = Rgb([u16::MAX, u16::MAX, sc/2]);
-            }
-        }
-
-        img.save_with_format(filename + ".png", ImageFormat::Png)
-           .expect("Image save error");
+        let spikes = μ.iter_spikes().map(|δ| {
+            let Loc([x, y]) = δ.x;
+            CSVSpike2 { x, y, alpha : δ.α }
+        });
+        let csv_f = format!("{}_spikes.csv", filename);
+        write_csv(spikes, csv_f).expect("CSV save error");
     }
 
     fn plot_into_file<
@@ -343,22 +163,14 @@
         g : &T1,
         grid : LinGrid<F, 2>,
         filename : String,
-        _explanation : String
     ) {
-        let [w, h] = grid.count;
-        let (rawdata, range) = rawdata_and_range(&grid, g);
-        let ramp = get_ramp(RAMP);
-        let im_iter = to_ramp::<F, u16, _>(&range, &ramp, rawdata.iter().cloned());
-        let mut img = ImageBuffer::new(w as u32, h as u32);
-        img.pixels_mut()
-           .zip(im_iter)
-           .for_each(|(p, v)| *p = v);
-        img.save_with_format(filename.clone() + ".png", ImageFormat::Png)
-           .expect("Image save error");
-        
-        let csv_iter = grid.into_iter().zip(rawdata.iter()).map(|(Loc(x), &v)| (x, v));
-        let csv_f = filename + ".txt";
-        write_csv(csv_iter, csv_f).expect("CSV save error");
+        let data = grid.into_iter().map(|p@Loc([x, y]) : Loc<F, 2>| CSVHelper2 {
+            x,
+            y,
+            f : g.apply(&p),
+        });
+        let csv_f = format!("{}.txt", filename);
+        write_csv(data, csv_f).expect("CSV save error");
     }
 
 }
@@ -386,12 +198,10 @@
     /// This calls [`PlotLookup::plot_into_file_spikes`] with a sequentially numbered file name.
     pub fn plot_spikes<T1, T2>(
         &mut self,
-        g_explanation : String,
-        g : &T1,
-        ω_explanation : String,
+        iter : usize,
+        g : Option<&T1>,
         ω : Option<&T2>,
-        tol : Option<Bounds<F>>,
-        μ : &DiscreteMeasure<Loc<F, N>, F>,
+        μ : &RNDM<F, N>,
     ) where T1 : RealMapping<F, N>,
             T2 : RealMapping<F, N>
     {
@@ -400,12 +210,11 @@
         }
         if self.plot_count < self.max_plots {
             PlotLookup::plot_into_file_spikes(
-                g_explanation, g,
-                ω_explanation, ω,
+                g,
+                ω,
                 self.grid,
-                tol,
                 μ,
-                format!("{}out{:03}", self.prefix, self.plot_count)
+                format!("{}out{:03}", self.prefix, iter)
             );
             self.plot_count += 1;
         }