charton API

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charton API / @chart-on/core / index / PriceScale

Class: PriceScale

Defined in: packages/core/src/scales.ts:465

Vertical scale. min/max live in coordinate space: price for normal/percent, log10(price) for log. Use minPrice/maxPrice for prices.

Constructors

Constructor

new PriceScale(options): PriceScale

Defined in: packages/core/src/scales.ts:514

Parameters

options

PriceScaleOptions

Returns

PriceScale

Properties

autoMargins

autoMargins: [number, number]

Defined in: packages/core/src/scales.ts:474

The margins (top, bottom) the chart sizes each frame, used for the null sides.

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autoScale

autoScale: boolean = true

Defined in: packages/core/src/scales.ts:469

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autoscaleRule

autoscaleRule: AutoscaleRule | null = null

Defined in: packages/core/src/scales.ts:502

Adjustments to the fitted data range; see AutoscaleRule.

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barRatio

barRatio: number | null = null

Defined in: packages/core/src/scales.ts:507

Coordinate units per bar width while the price-to-bar ratio is locked (NaN: lock at the current ratio on the next applyBarRatio); null when unlocked.

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bounds

bounds: { high?: number; low?: number; } | null = null

Defined in: packages/core/src/scales.ts:498

Prices the visible range must stay within (viewport bounds); either end may be missing.

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fixedRange

fixedRange: { max: number; min: number; } | null = null

Defined in: packages/core/src/scales.ts:500

While autoscale is on, show exactly this price range instead of fitting the data.

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height

height: number = 0

Defined in: packages/core/src/scales.ts:466

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id

readonly id: string

Defined in: packages/core/src/scales.ts:478

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invert

invert: boolean = false

Defined in: packages/core/src/scales.ts:477

Higher prices lower down.

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link

link: PriceScale | null = null

Defined in: packages/core/src/scales.ts:489

Scale this one follows (e.g. a compared symbol's scale linked to the main one): it takes the same mode, and in percent and indexed modes both fit one shared percent range, so their lines compare directly.

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marginBottom

marginBottom: number | null

Defined in: packages/core/src/scales.ts:472

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marginTop

marginTop: number | null

Defined in: packages/core/src/scales.ts:471

Fractions of the height left empty above/below the data; null for a side the chart sizes.

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max

max: number = 1

Defined in: packages/core/src/scales.ts:468

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min

min: number = 0

Defined in: packages/core/src/scales.ts:467

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mode

mode: PriceScaleMode = 'normal'

Defined in: packages/core/src/scales.ts:475

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noPositiveData

noPositiveData: boolean = false

Defined in: packages/core/src/scales.ts:496

Log mode with visible data but none of it above zero (set by the chart). Autoscale then keeps the last range.

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percentBase

percentBase: number = 1

Defined in: packages/core/src/scales.ts:481

Reference price for percent and indexed modes, resolved each frame from percentFrom.

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percentFrom

percentFrom: PercentBase = 'firstVisible'

Defined in: packages/core/src/scales.ts:483

Where percentBase comes from (the percentBase setting); a linked scale follows its root's.

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side

side: PriceScaleSide

Defined in: packages/core/src/scales.ts:479

---

smooth

smooth: boolean = false

Defined in: packages/core/src/scales.ts:491

Ease autoscale changes instead of jumping (set by the chart).

Accessors

isLog

Get Signature

get isLog(): boolean

Defined in: packages/core/src/scales.ts:521

Returns

boolean

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maxPrice

Get Signature

get maxPrice(): number

Defined in: packages/core/src/scales.ts:539

Returns

number

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minPrice

Get Signature

get minPrice(): number

Defined in: packages/core/src/scales.ts:535

Returns

number

Methods

applyBarRatio()

applyBarRatio(barSpacing): void

Defined in: packages/core/src/scales.ts:734

With a locked ratio, set the span for barSpacing around the current centre, so zooming time scales prices too and angles stay put.

Parameters

barSpacing

number

Returns

void

---

applyRule()

applyRule(r): void

Defined in: packages/core/src/scales.ts:641

Apply autoscaleRule to a price range fitted from the data, in place. Without a rule, or for a fixed range (which wins), r is left as it is.

Parameters

r

[number, number]

Returns

void

---

fit()

fit(lo, hi): void

Defined in: packages/core/src/scales.ts:607

Fit [lo, hi] (prices) including margins; no-op in manual mode. In log mode bounds at or below zero cannot be shown: a non-positive hi keeps the current range, and a non-positive lo fits around hi alone.

Parameters

lo

number

hi

number

Returns

void

---

follow()

follow(root): void

Defined in: packages/core/src/scales.ts:724

Show the same percent range as root shows, exactly (a linked scale whose root is not fitting the data: manual, fixed or ratio-locked).

Parameters

root

PriceScale

Returns

void

---

fromCoord()

fromCoord(coord): number

Defined in: packages/core/src/scales.ts:531

Coordinate space → price.

Parameters

coord

number

Returns

number

---

fromIndexed()

fromIndexed(value): number

Defined in: packages/core/src/scales.ts:598

Parameters

value

number

Returns

number

---

fromPercent()

fromPercent(pct): number

Defined in: packages/core/src/scales.ts:589

Parameters

pct

number

Returns

number

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inBounds()

inBounds(min, max): [number, number]

Defined in: packages/core/src/scales.ts:680

The range min to max (coordinates) moved inside bounds: slid in without changing its span, or the whole band when the span is wider.

Parameters

min

number

max

number

Returns

[number, number]

---

keepInBounds()

keepInBounds(): void

Defined in: packages/core/src/scales.ts:692

Keep the visible range inside bounds.

Returns

void

---

lockRatio()

lockRatio(ratio): void

Defined in: packages/core/src/scales.ts:715

Lock the price-to-bar ratio at ratio, or at the current one with NaN; null unlocks.

Parameters

ratio

number | null

Returns

void

---

pan()

pan(dy): void

Defined in: packages/core/src/scales.ts:782

Positive dy drags content down; switches to manual mode.

Parameters

dy

number

Returns

void

---

priceToY()

priceToY(price): number

Defined in: packages/core/src/scales.ts:563

Parameters

price

number

Returns

number

---

setMode()

setMode(mode): void

Defined in: packages/core/src/scales.ts:543

Parameters

mode

PriceScaleMode

Returns

void

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setRange()

setRange(lo, hi, animate?): void

Defined in: packages/core/src/scales.ts:700

Show prices lo to hi exactly and switch to manual mode, easing there with animate. A locked price-to-bar ratio is taken again from the new range.

Parameters

lo

number

hi

number

animate?

boolean = false

Returns

void

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step()

step(dt): boolean

Defined in: packages/core/src/scales.ts:750

Ease towards the last fit target, or a setRange target; true while still moving.

Parameters

dt

number

Returns

boolean

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toCoord()

toCoord(price): number

Defined in: packages/core/src/scales.ts:526

Price → coordinate space.

Parameters

price

number

Returns

number

---

toIndexed()

toIndexed(price): number

Defined in: packages/core/src/scales.ts:594

price indexed to 100 at percentBase.

Parameters

price

number

Returns

number

---

toPercent()

toPercent(price): number

Defined in: packages/core/src/scales.ts:585

Percent change of price against percentBase.

Parameters

price

number

Returns

number

---

yToPrice()

yToPrice(y): number

Defined in: packages/core/src/scales.ts:568

Parameters

y

number

Returns

number

---

yTransform()

yTransform(): [number, number]

Defined in: packages/core/src/scales.ts:579

Affine coefficients so that y = coord(price) * scale + offset.

Returns

[number, number]

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zoom()

zoom(factor, anchorY?): void

Defined in: packages/core/src/scales.ts:771

Scale around the price at anchorY; switches to manual mode, and a locked ratio follows.

Parameters

factor

number

anchorY?

number = ...

Returns

void