Price Lines

A price line is a horizontal line drawn across a series at a specific price. Use price lines when you need to annotate fixed levels (entry, stop, target, strike) or track a live, table-driven value such as a moving threshold. Use tvl.price_line() for a static level (price=100) or for a Deephaven-extension column-driven level (column="ThresholdCol") where the line tracks the last row of a named column as the table ticks. The returned PriceLine object goes onto a series via the price_lines= argument.

What are price lines useful for?

Marking levels: Entry, stop, and target levels on a trade can be drawn as static price lines so they sit alongside the candlestick body.
Showing thresholds: A risk threshold or alert level becomes a single horizontal line on the chart pane.
Following live values: A column-driven price line tracks the most recent row of a table, which works well for “current best bid” or “current VWAP” on a ticking stream.
Annotating with labels: Each price line carries a title (drawn on the pane) and an axis label with its own colors, so the level can describe itself.

Examples

Add a simple horizontal line at a price

The minimal price line. Pass it to a series via price_lines=[...].

import deephaven.plot.tradingview_lightweight as tvl

ohlc = tvl.data.ohlc()

target = tvl.price_line(price=104.0, color="#2e7d32")

simple_line = tvl.candlestick(ohlc, price_lines=[target])

A green horizontal line sits at 104.0 across the entire chart.

Style a price line

Most visual properties of a PriceLine are independent: color, width, dashing, and whether the line itself is drawn. The supported widths are 1, 2, 3, 4; styles come from LineStyle ("solid", "dotted", "dashed", "large_dashed", "sparse_dotted").

import deephaven.plot.tradingview_lightweight as tvl

ohlc = tvl.data.ohlc()

styled = tvl.price_line(
    price=104.0,
    color="#d32f2f",
    line_width=3,
    line_style="dashed",
    line_visible=True,
    id="stop-loss",
)

styled_line = tvl.candlestick(ohlc, price_lines=[styled])

A dashed red line at 104.0, three pixels wide.

Add a title and an axis label

The title is drawn next to the line on the chart pane. The axis label (which sits on the price scale) is controlled by axis_label_visible, axis_label_color, and axis_label_text_color.

import deephaven.plot.tradingview_lightweight as tvl

ohlc = tvl.data.ohlc()

labeled = tvl.price_line(
    price=98.0,
    color="#1976d2",
    line_width=2,
    line_style="solid",
    title="Support",
    axis_label_visible=True,
    axis_label_color="#1976d2",
    axis_label_text_color="#ffffff",
)

labeled_line = tvl.candlestick(ohlc, price_lines=[labeled])

The line is labeled Support on the chart and 98.00 on the axis (with a blue background).

Draw many price lines at once

A list of price lines can be attached to one series. This is the natural way to show a set of strikes, ladder levels, or stop placements.

import deephaven.plot.tradingview_lightweight as tvl

ohlc = tvl.data.ohlc()

ladder = [
    tvl.price_line(price=p, color=c, line_style=style, title=label)
    for p, c, style, label in [
        (104.0, "#2e7d32", "solid",       "Target"),
        (102.0, "#558b2f", "dotted",      "Trim"),
        (100.0, "#1976d2", "dashed",      "Entry"),
        ( 98.0, "#ef6c00", "large_dashed","Trail stop"),
        ( 96.0, "#c62828", "sparse_dotted","Hard stop"),
    ]
]

ladder_chart = tvl.candlestick(ohlc, price_lines=ladder)

Five horizontal lines, each using a different LineStyle value, label the trading ladder. Notice the loop covers all five styles in LineStyle.

Hide the line, keep the axis label

line_visible=False removes the horizontal stroke from the pane but keeps the axis label on the price scale. This is useful when you want a value annotation without cluttering the chart body.

import deephaven.plot.tradingview_lightweight as tvl

ohlc = tvl.data.ohlc()

invisible = tvl.price_line(
    price=100.0,
    line_visible=False,
    axis_label_visible=True,
    axis_label_color="#1976d2",
    axis_label_text_color="#ffffff",
    title="Par",
    id="par-level",
)

labelonly_chart = tvl.candlestick(ohlc, price_lines=[invisible])

The chart shows the axis tag for 100.00 with no line drawn through the pane.

Track a live column value

This is the Deephaven extension to price_line(). Pass column= instead of price= and the line tracks the last row of that column. When the source table ticks, the price line moves automatically.

import deephaven.plot.tradingview_lightweight as tvl
from deephaven.updateby import rolling_avg_tick

ohlc = tvl.data.ohlc()
# 20-period moving average — last row is the current value.
ohlc_w_avg = ohlc.update_by(
    ops=[rolling_avg_tick(cols=["AvgClose = Close"], rev_ticks=20)],
)

live = tvl.price_line(
    column="AvgClose",
    color="#ef6c00",
    line_width=2,
    line_style="solid",
    title="MA(20)",
)

live_line = tvl.candlestick(ohlc_w_avg, price_lines=[live])

The orange line tracks the 20-period moving average of Close. It is mutually exclusive with price=; setting both, or neither, raises ValueError.

Pick the source for the built-in last-price line

Separate from user-added price lines, every series has an automatic “last price” horizontal line, styled with last_price_line=tvl.last_price_line(...) (returns a LastPriceLine). Its source (a PriceLineSource value) picks whether it follows the last bar or the last visible bar.

import deephaven.plot.tradingview_lightweight as tvl

ohlc = tvl.data.ohlc()

# Follow the last bar in the data, regardless of scroll position.
last_bar = tvl.line(
    ohlc, timestamp="Timestamp", value="Close",
    color="#1976d2",
    last_price_line=tvl.last_price_line(
        visible=True,
        source="last_bar",
        color="#1976d2",
        width=2,
        style="dotted",
    ),
)

# Follow the last visible bar — moves as you scroll.
last_visible = tvl.line(
    ohlc, timestamp="Timestamp", value="Open",
    color="#d32f2f",
    last_price_line=tvl.last_price_line(
        visible=True,
        source="last_visible",
        color="#d32f2f",
        width=2,
        style="dashed",
    ),
)

source_chart = tvl.chart(last_bar, last_visible)

Two series with different source values demonstrate both members of the PriceLineSource enum ("last_bar", "last_visible").

API Reference

Provide either price (static value) or column (dynamic, tracking the last-row value of the named column in the series' table).

Returns: PriceLine A PriceLine instance.

Raises: ValueError -- If neither or both of price and column are supplied.

Parameters	Type	Default	Description
price	Optional[float]	None	Static price level. Mutually exclusive with column.
color	Optional[Color]	None	Line color (CSS color string).
line_width	Optional[LineWidth]	None	Line thickness in pixels (1–4).
line_style	Optional[LineStyle]	None	Dash pattern; see LineStyle.
line_visible	Optional[bool]	None	Whether the horizontal line rule is drawn (default True in TV-LW). Set to False to show only the axis label.
axis_label_visible	Optional[bool]	None	Whether the axis label is shown on the price scale.
title	Optional[str]	None	Short text drawn on the chart pane next to the line.
axis_label_color	Optional[Color]	None	Background color of the price-scale axis label.
axis_label_text_color	Optional[Color]	None	Text color of the price-scale axis label.
id	Optional[str]	None	Optional string identifier for the price line.
column	Optional[str]	None	Deephaven extension — column name whose last-row value sets the price level dynamically. Mutually exclusive with price.

Create a LastPriceLine for a series' last_price_line= argument.

Returns: LastPriceLine A last-price-line config for last_price_line=.

Parameters	Type	Default	Description
visible	bool \| None	None	Show the last-price line (TVL default True).
source	Literal['last_bar', 'last_visible'] \| None	None	Which bar drives the line; see PriceLineSource.
width	Literal[1, 2, 3, 4] \| None	None	Stroke width in pixels; see LineWidth.
color	Literal['gray-50', 'gray-75', 'gray-100', 'gray-200', 'gray-300', 'gray-400', 'gray-500', 'gray-600', 'gray-700', 'gray-800', 'gray-900', 'red-100', 'red-200', 'red-300', 'red-400', 'red-500', 'red-600', 'red-700', 'red-800', 'red-900', 'red-1000', 'red-1100', 'red-1200', 'red-1300', 'red-1400', 'orange-100', 'orange-200', 'orange-300', 'orange-400', 'orange-500', 'orange-600', 'orange-700', 'orange-800', 'orange-900', 'orange-1000', 'orange-1100', 'orange-1200', 'orange-1300', 'orange-1400', 'yellow-100', 'yellow-200', 'yellow-300', 'yellow-400', 'yellow-500', 'yellow-600', 'yellow-700', 'yellow-800', 'yellow-900', 'yellow-1000', 'yellow-1100', 'yellow-1200', 'yellow-1300', 'yellow-1400', 'chartreuse-100', 'chartreuse-200', 'chartreuse-300', 'chartreuse-400', 'chartreuse-500', 'chartreuse-600', 'chartreuse-700', 'chartreuse-800', 'chartreuse-900', 'chartreuse-1000', 'chartreuse-1100', 'chartreuse-1200', 'chartreuse-1300', 'chartreuse-1400', 'celery-100', 'celery-200', 'celery-300', 'celery-400', 'celery-500', 'celery-600', 'celery-700', 'celery-800', 'celery-900', 'celery-1000', 'celery-1100', 'celery-1200', 'celery-1300', 'celery-1400', 'green-100', 'green-200', 'green-300', 'green-400', 'green-500', 'green-600', 'green-700', 'green-800', 'green-900', 'green-1000', 'green-1100', 'green-1200', 'green-1300', 'green-1400', 'seafoam-100', 'seafoam-200', 'seafoam-300', 'seafoam-400', 'seafoam-500', 'seafoam-600', 'seafoam-700', 'seafoam-800', 'seafoam-900', 'seafoam-1000', 'seafoam-1100', 'seafoam-1200', 'seafoam-1300', 'seafoam-1400', 'cyan-100', 'cyan-200', 'cyan-300', 'cyan-400', 'cyan-500', 'cyan-600', 'cyan-700', 'cyan-800', 'cyan-900', 'cyan-1000', 'cyan-1100', 'cyan-1200', 'cyan-1300', 'cyan-1400', 'blue-100', 'blue-200', 'blue-300', 'blue-400', 'blue-500', 'blue-600', 'blue-700', 'blue-800', 'blue-900', 'blue-1000', 'blue-1100', 'blue-1200', 'blue-1300', 'blue-1400', 'indigo-100', 'indigo-200', 'indigo-300', 'indigo-400', 'indigo-500', 'indigo-600', 'indigo-700', 'indigo-800', 'indigo-900', 'indigo-1000', 'indigo-1100', 'indigo-1200', 'indigo-1300', 'indigo-1400', 'purple-100', 'purple-200', 'purple-300', 'purple-400', 'purple-500', 'purple-600', 'purple-700', 'purple-800', 'purple-900', 'purple-1000', 'purple-1100', 'purple-1200', 'purple-1300', 'purple-1400', 'fuchsia-100', 'fuchsia-200', 'fuchsia-300', 'fuchsia-400', 'fuchsia-500', 'fuchsia-600', 'fuchsia-700', 'fuchsia-800', 'fuchsia-900', 'fuchsia-1000', 'fuchsia-1100', 'fuchsia-1200', 'fuchsia-1300', 'fuchsia-1400', 'magenta-100', 'magenta-200', 'magenta-300', 'magenta-400', 'magenta-500', 'magenta-600', 'magenta-700', 'magenta-800', 'magenta-900', 'magenta-1000', 'magenta-1100', 'magenta-1200', 'magenta-1300', 'magenta-1400', 'negative', 'notice', 'positive', 'info', 'accent', 'accent-100', 'accent-200', 'accent-300', 'accent-400', 'accent-500', 'accent-600', 'accent-700', 'accent-800', 'accent-900', 'accent-1000', 'accent-1100', 'accent-1200', 'accent-1300', 'accent-1400', 'bg', 'content-bg', 'subdued-content-bg', 'surface-bg', 'fg'] \| str \| None	None	Line CSS color (empty string uses the series color).
style	Literal['solid', 'dotted', 'dashed', 'large_dashed', 'sparse_dotted'] \| None	None	Dash pattern; see LineStyle.