Struct PositionStack 

pub struct PositionStack {
    pub vjust: f64,
}

Stack bars/areas on top of each other (ggplot2’s position_stack(vjust = )).

vjust places the row’s y within its stacked segment: 1 (the default) puts it at the segment’s top — the pre-B3-4 behaviour, and byte-identical (no ymax column is written). Anything else writes y = (1 − vjust)·ymin + vjust·ymax and an ymax column holding the segment’s top, so e.g. vjust(0.5) centres a label in its segment.

PositionStack is also usable as a bare value (vjust 1, as before the struct gained fields) via the PositionStack const.

Fields

vjust: f64

Implementations

impl PositionStack

pub fn with_vjust(self, vjust: f64) -> Self

Place y within each stacked segment (0 = bottom, 0.5 = middle, 1 = top, the default).

Trait Implementations

impl Clone for PositionStack

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 PositionStack

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

Formats the value using the given formatter.

impl Default for PositionStack

fn default() -> Self

Returns the “default value” for a type.

impl PartialEq for PositionStack

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

Equality operator ==.

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

Inequality operator !=.

impl Position for PositionStack

fn compute(&self, data: &mut DataFrame, _params: &PositionParams)

Adjust positions for data.

fn name(&self) -> &str

fn per_panel(&self) -> bool

Whether this position must run separately per facet panel rather than once on the pooled rows before facets are split (B3-3, D8). Default false. PositionStack/PositionFill override this to true — a shared x category’s stack height must not mix rows from different panels. PositionDodge/PositionDodge2/PositionJitter also override this to true (sipemu/ggplot-rs#153): ggplot2 computes a dodge’s group count/offset via compute_panel (per panel), and position_jitter’s default width/height — 40% of resolution() — is likewise measured from each panel’s own x/y, not the rows pooled across panels (verified against ggplot2 4.0.3 with layer_data() on faceted plots; see tests/position_panels_r.rs).

fn validate(&self, warnings: &mut Vec<String>)

Validate this position’s own parameters once per layer (D2); default no-op. Implementations push a warning and fall back to a sane default rather than panicking or silently miscomputing.

fn group_order(&self, _data: &DataFrame) -> Option<Vec<String>>

The whole layer’s group rank order (first-appearance, pre-panel- split), for a per_panel position whose group ranking must come from the whole layer even though its per-x counting stays per-panel (review #167 finding 2; sipemu/ggplot-rs#153). build::compute_position_per_panel calls this on the pooled data before splitting and threads the result through PositionParams::group_order to every panel’s compute call. Default None — positions that don’t need this (stack/fill/ jitter) are unaffected.

impl StructuralPartialEq for PositionStack