You can find poloto on github and crates.io.
Documentation at docs.rs
A simple 2D plotting library that outputs graphs to SVG that can be styled using CSS.
Poloto graphs can be stylized using css either directly in the SVG, or from inside of html with an embedded svg. The latter allows the user to dynamically match the svg to their website's theme. The user can take full advantage of CSS, adding highlight on hover, animation, shadows, strokes, etc. Check out the github examples to see this. The latest graph outputs of the examples can be found in the assets folder.
You can see it in action in this rust book broccoli-book
Gaussian Example
use poloto::build;
fn main() {
let gau = |sigma: f64, mu: f64| {
use std::f64::consts::TAU;
let s = sigma.powi(2);
let k = (sigma * TAU).sqrt().recip();
move |x: f64| [x, (-0.5 * (x - mu).powi(2) / s).exp() * k]
};
let xs = poloto::util::range_iter([-5.0, 5.0], 200);
let plots = poloto::plots!(
build::plot("σ=1.0").line(xs.clone().map(gau(1.0, 0.0))),
build::plot("σ=0.5").line(xs.clone().map(gau(0.5, 0.0))),
build::plot("σ=0.3").line(xs.clone().map(gau(0.3, 0.0)))
);
poloto::data(poloto::plots!(build::origin(), plots))
.build_and_label(("gaussian", "x", "y"))
.append_to(poloto::header().light_theme())
.render_stdout();
}
Output
Collatz Example
use hypermelon::prelude::*;
use poloto::build;
fn main() {
let collatz = |mut a: i128| {
std::iter::from_fn(move || {
if a == 1 {
None
} else {
a = if a % 2 == 0 { a / 2 } else { 3 * a + 1 };
Some(a)
}
})
.fuse()
};
let svg = poloto::header().with_viewbox_width(1200.0);
let opt = poloto::render::render_opt()
.with_tick_lines([true, true])
.with_viewbox(svg.get_viewbox())
.move_into();
let style =
poloto::render::Theme::dark().append(".poloto_line{stroke-dasharray:2;stroke-width:2;}");
let a = (1000..1006).map(|i| build::plot(format!("c({})", i)).line((0..).zip(collatz(i))));
poloto::data(poloto::plots!(poloto::build::origin(), a))
.map_opt(|_| opt)
.build_and_label(("collatz", "x", "y"))
.append_to(svg.append(style))
.render_stdout();
}
Output
Timestamp Example
use poloto::build;
use poloto::num::timestamp::UnixTime;
fn main() {
let timezone = &chrono::Utc;
use chrono::TimeZone;
let data = [
(7.61, "05 August 1901"),
(7.69, "23 July 1921"),
(7.76, "07 July 1924"),
(7.89, "13 June 1925"),
(7.90, "07 July 1928"),
(7.93, "09 September 1928"),
(7.98, "27 October 1931"),
(8.13, "25 May 1935"),
(8.21, "12 August 1960"),
(8.24, "27 May 1961"),
(8.28, "16 July 1961"),
(8.31, "10 June 1962"),
(8.33, "25 May 1963"),
(8.34, "12 September 1964"),
(8.35, "29 May 1965"),
(8.35, "19 October 1967"),
(8.90, "18 October 1968"),
(8.95, "30 August 1991"),
];
let data = data.map(|(x, y)| {
let d = timezone.from_utc_date(&chrono::NaiveDate::parse_from_str(y, "%d %B %Y").unwrap());
(UnixTime::from(d), x)
});
let plots = poloto::plots!(
build::plot("").line(data),
build::markers([], [0.0])
);
poloto::data(plots)
.build_and_label((
"Long Jump world record progression",
"Date",
"Mark (in meters)",
))
.append_to(poloto::header().light_theme())
.render_stdout();
}
Output
Custom Ticks Example
use hypermelon::format_move;
use poloto::build;
fn main() {
let trend = vec![
0, 0, 0, 0, 0, 3, 5, 5, 10, 20, 50, 60, 70, 50, 40, 34, 34, 20, 10, 20, 10, 4, 2, 0,
];
let plots = poloto::plots!(
build::plot("").histogram((0..).zip(trend)),
build::markers([24], [])
);
let data = poloto::data(plots);
let ticks =
poloto::ticks::from_iter((0..).step_by(6)).with_tick_fmt(|&v| format_move!("{} hr", v));
data.map_xticks(|_| ticks)
.build_and_label(("title", "x", "y"))
.append_to(poloto::header().light_theme())
.render_stdout();
}
Output
Bar example
fn main() {
let data = [
(20, "potato"),
(14, "broccoli"),
(53, "pizza"),
(30, "avocado"),
];
poloto::build::bar::gen_simple("", data, [0])
.label(("Comparison of Food Tastiness", "Tastiness", "Foods"))
.append_to(poloto::header().light_theme())
.render_stdout();
}
Output
Styling example
use hypermelon::prelude::*;
use poloto::{build, prelude::OutputZip};
fn main() {
let theme = poloto::render::Theme::light();
let theme =
theme.append(".poloto0.poloto_histo.poloto_imgs{fill:red;stroke:black;stroke-width:2px}");
let theme = theme.append(".poloto0.poloto_histo.poloto_imgs>*{rx:20px;ry:20px}");
let theme = theme.append(".poloto0.poloto_legend.poloto_text{fill:blue;}");
let theme = theme.append(".poloto_line.poloto_imgs.poloto_plot{stroke:purple;stroke-width:20px;stroke-dasharray:40px}");
let theme = theme.append(".poloto_line.poloto_imgs.poloto_legend{stroke:purple;stroke-width:10px;stroke-dasharray:10px}");
let theme = theme.append(".poloto_scatter.poloto_plot{fill:purple;stroke-width:20px;}");
let theme = theme.append(".poloto_scatter.poloto_plot{fill:purple;stroke-width:20px;}");
let theme = theme.append(
".poloto_name.poloto_x{fill:orange;stroke-width:20px;font-size:30px;font-style: italic;}",
);
let theme = theme.append(".poloto_background{fill:darkslategray;}");
let theme = theme.append(".poloto_text{fill: peru;}");
let theme = theme.append(".poloto_imgs.poloto_ticks{stroke:springgreen;}");
let x = (0..50).map(|x| (x as f64 / 50.0) * 10.0);
let data = poloto::plots!(
build::plot("sin-10").histogram(x.clone().step_by(3).zip_output(|x| x.sin() - 10.)),
build::plot("cos").line(x.clone().zip_output(|x| x.cos())),
build::plot("sin-5").scatter(x.clone().step_by(3).zip_output(|x| x.sin() - 5.))
);
poloto::data(data)
.build_and_label((
"Demo: you can change the style of the svg file itself!",
"x axis",
"y axis",
))
.append_to(poloto::header().append(theme))
.render_stdout();
}
Output
Usecases
Poloto converts each plot into svg elements like circles. Because of this its not really suitable for plots with many many plots. For those you might want to use a library to lets you plot directly to a png/jpg image instead. You can certainly rasterize the generated svg image, but generating and displaying the svg wont be all that efficient if there are a ton of plots.
cloned vs buffered plot iterators
poloto runs through plot iterators twice. Once to get the min/max bounds, and a second time to scale all
the plots by those min/max bounds. There are two ways to do this. One is to just clone the iterator, and consume
both. The second way is to accumulate the items from one iterator into a Vec<>, and then just iterate over that vec.
By default, poloto will use a Vec backed buffer. However, you can configure it to clone the iterator instead.
let data=[[1.0,2.0],[2.0,3.0]];
poloto::build::plot("").line(data);
let it=(0..).take(10).zip(5..);
poloto::build::plot("").line(poloto::build::cloned(it));
Using the cloned method has pros and cons. The user has more control and can reduce memory usage.
However they might accidentally increase memory usage.
Escape protection
If a user tried to inject html through the title/xname/yname/tick format/ or plot names, the html escapes
will get turned into their encoded values. This protection is provided by the hypermelon dependency crate.
CSS Usage Example
See the graphs in this report: broccoli_book
CSS classes
poloto[n]fill - If the n'th plot requires fill. (e.g. linefill or histogram)poloto[n]stroke - If the n'th plot requires stroke. (e.g. line or scatter)
Can I change the styling of the plots?
Yes! You can harness the power of CSS both in the svg, or outside
in html with an embedded svg. Some things you can do:
- Change the color scheme to fit your html theme.
- Highlight one plot, make it dashed, or add hover effect
- Animate things using @keyframes
The Plotter struct documents which css classes you can modify for the graph as a whole.
Each plot function documents which css classes you can modify to change that specific plot.
Scatter plots are done using SVG paths made up of lines of zero length. This allows you to change
the radius of the scatter dots by changing the stroke width.
Formatting Tick Intervals
Poloto will first print intervals in normal decimal at the precision required to capture the differences
in the step size between the intervals. If the magnitude of a number is detected to be too big or small, it
may switch to scientific notation, still at the required precision. It will only switch if the scientific
notation version is actually less characters than the normal decimal format which is not always the case
when you consider the precision that might be required to capture the step size.
Even with the above system, there are cases where the numbers all have a really big magnitude, but
are all really close together (small step size). In this case, there isn't really a good way to format it.
In these cases, poloto will fall back to making the number relative to the first number.
How to render to png?
You can use resvg. Install that, and then run a command similar to:
resvg -w 1200 target/assets/collatz.svg target/assets/collatz.png
Output
