Struct Scale 

pub struct Scale {
    pub kind: ScaleKind,
    pub domain_min: f64,
    pub domain_max: f64,
    pub range_min: f64,
    pub range_max: f64,
    pub categories: Vec<String>,
    pub log_base: f64,
    pub band: f64,
    pub count: usize,
}

A mapping from data values to pixel positions.

One scale serves one axis. The scale knows the data domain (the range of values the data cover) and the pixel range (the extent of the grid along the axis), and maps between them.

Fields

kind: ScaleKind

The kind of the scale.

domain_min: f64

The lower end of the data domain.

domain_max: f64

The upper end of the data domain.

range_min: f64

The lower end of the pixel range.

range_max: f64

The upper end of the pixel range.

categories: Vec<String>

The categories of an ordinal scale.

log_base: f64

The base of a logarithmic scale.

band: f64

The width of one band of an ordinal scale, in pixels.

A band is the space one category occupies. It is larger than the distance between two category centres by exactly one band, which is what lets a bar chart draw a bar that fills its band without spilling into the neighbouring one.

count: usize

The number of categories of an ordinal scale.

The count is kept apart from the names because the two are not the same: a chart over a million unnamed points has a million categories and not one name.

Implementations

impl Scale

Inherent implementation of Scale.

pub fn linear( domain_min: f64, domain_max: f64, range_min: f64, range_max: f64, ) -> Self

Returns a linear scale covering the given domain and range.

Arguments

• f64 - A 64-bit float (f64).

pub fn log( domain_min: f64, domain_max: f64, range_min: f64, range_max: f64, base: f64, ) -> Self

Returns a logarithmic scale covering the given domain and range.

Arguments

• f64 - A 64-bit float (f64).

pub fn category( categories: Vec<String>, range_min: f64, range_max: f64, band: f64, ) -> Self

Returns an ordinal scale over the given categories.

range_min and range_max are the positions of the centres of the first and the last band, and band is the width of one band.

Arguments

• Vec<String> - A Vec<String> parameter.
• f64 - A 64-bit float (f64).

pub fn category_count( count: usize, range_min: f64, range_max: f64, band: f64, ) -> Self

Returns an ordinal scale over the given number of categories.

The scale has no names: it is used for a chart whose points are not named, where keeping a million empty strings would be pure waste.

Arguments

• usize - A non-negative integer (usize).
• f64 - A 64-bit float (f64).

pub fn map(&self, value: f64) -> f64

Maps a data value to a pixel position.

Values outside the domain are clamped to the range, which is what keeps a series that overflows its axis from drawing outside the grid.

Arguments

• f64 - A 64-bit float (f64).

Returns

• f64 - A 64-bit float.

pub fn invert(&self, pixel: f64) -> f64

Maps a pixel position back to a data value.

Arguments

• f64 - A 64-bit float (f64).

Returns

• f64 - A 64-bit float.

pub fn band_width(&self) -> f64

Returns the width of one band of an ordinal scale, in pixels.

Returns 0.0 for a scale that is not ordinal.

Returns

• f64 - A 64-bit float.

pub fn is_ordinal(&self) -> bool

Returns true when the scale maps ordinal values.

Returns

• bool - A boolean.

impl Scale

pub fn get_kind(&self) -> ScaleKind

pub fn get_mut_kind(&mut self) -> &mut ScaleKind

pub fn set_kind(&mut self, val: ScaleKind) -> &mut Self

pub fn get_domain_min(&self) -> f64

pub fn get_mut_domain_min(&mut self) -> &mut f64

pub fn set_domain_min(&mut self, val: f64) -> &mut Self

pub fn get_domain_max(&self) -> f64

pub fn get_mut_domain_max(&mut self) -> &mut f64

pub fn set_domain_max(&mut self, val: f64) -> &mut Self

pub fn get_range_min(&self) -> f64

pub fn get_mut_range_min(&mut self) -> &mut f64

pub fn set_range_min(&mut self, val: f64) -> &mut Self

pub fn get_range_max(&self) -> f64

pub fn get_mut_range_max(&mut self) -> &mut f64

pub fn set_range_max(&mut self, val: f64) -> &mut Self

pub fn get_categories(&self) -> &Vec<String>

pub fn get_mut_categories(&mut self) -> &mut Vec<String>

pub fn set_categories(&mut self, val: Vec<String>) -> &mut Self

pub fn get_log_base(&self) -> f64

pub fn get_mut_log_base(&mut self) -> &mut f64

pub fn set_log_base(&mut self, val: f64) -> &mut Self

pub fn get_band(&self) -> f64

pub fn get_mut_band(&mut self) -> &mut f64

pub fn set_band(&mut self, val: f64) -> &mut Self

pub fn get_count(&self) -> usize

pub fn get_mut_count(&mut self) -> &mut usize

pub fn set_count(&mut self, val: usize) -> &mut Self

Trait Implementations

impl Clone for Scale

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Scale

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl PartialEq for Scale

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for Scale