HashTrace and HashTable

Cargo featurefeatures = ["cs"]

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HashTrace::record(buckets, &keys) starts a table with separate chaining: a key goes to bucket key mod buckets (Euclidean, so negative keys land in a bucket too) and is added to the end of its chain. insert, find and remove show the hash, walk the chain one entry a step and note each comparison; a key that is already there is not added twice. HashTable draws the buckets as a column of index cells with each chain to its right, linked by arrows. Gallery scene: HashTable.

HashTable demo, first frame — `HashTable` 12.5 s

use fframes_kit::prelude::*;

let table = HashTrace::record(5, &[12, 7, 3]).insert(17).find(9).finish();
let last = table.steps().last().unwrap();
assert_eq!(last.buckets[2].len(), 3);
assert_eq!(last.note, "9 is not there");

fn draw_table<'a>(ui: &mut Ui<'a, '_, '_>, trace: &'a HashTrace) -> Svgr<'a> {
    ui.show(HashTable { trace: Some(trace), step_time: 0.6, ..ui.defaults() })
}

API

Components are plain structs. Set the fields you need and fill the rest with ..ui.defaults(): the defaults below come from the current theme (theme. values are fields of Theme).

HashTable

A hash table: a column of numbered buckets, each height pixels tall and gap apart, with its chain of entries (cell pixels wide, link pixels apart) linked to its right, centred on center (units of ui.space). It plays a HashTrace, one step every step_time seconds from delay: the bucket a key hashes to lights up, the entries walked light up one by one, a found entry turns green, new entries slide in at the end of their chain and removed ones leave as the chain closes. The whole figure fades with enter and exit.

Field	Type	Default	Description
`trace`	`Option<&HashTrace>`	`None`	The recorded steps to play (`HashTrace`); `None` draws nothing.
`delay`	`f32`	`0.0`	Seconds after the container’s start before the first step.
`step_time`	`f32`	`0.7`	Seconds each step of the trace takes.
`center`	`(f64, f64)`	`(0.0, 0.0)`	The middle of the table, in units of `ui.space`.
`bucket`	`f32`	`64.0`	Width of a bucket in pixels.
`cell`	`f32`	`96.0`	Width of an entry in a chain in pixels.
`height`	`f32`	`56.0`	Height of a bucket and of its entries in pixels.
`gap`	`f32`	`14.0`	Space between neighbouring buckets in pixels.
`link`	`f32`	`48.0`	Length of the arrow between a bucket and its first entry, and between entries, in pixels.
`notes`	`bool`	`true`	Whether the step’s note is written under the table.
`colors`	`CellColors`	`CellColors::themed(theme)`	Colours of the entries in each state (walked, found, moved).
`bucket_color`	`Color`	`theme.colors.surface`	Colour of a bucket at rest; the bucket a key hashes to takes `colors.compare`.
`link_color`	`Color`	`theme.colors.text`	Colour of the arrows that link a chain.
`index_color`	`Color`	`theme.colors.muted`	Colour of the bucket numbers.
`value_style`	`TextStyle`	`value_style`	The font of the keys in the entries.
`small_style`	`TextStyle`	`theme.typography.caption`	The font of the bucket numbers and notes.
`enter`	`Option<FadeIn>`	`None`	Fade in at the start; `None` for none.
`exit`	`Option<FadeOut>`	`None`	Fade out before the end; `None` for none.

Feature cs · Source