An OHLC (Open-High-Low-Close) bar chart displays financial price data using vertical bars with horizontal tick marks. Each bar shows the price range from high to low as a thin vertical line, with a left tick indicating the opening price and a right tick indicating the closing price. Unlike candlestick charts that use colored bodies, OHLC bars provide a cleaner, less cluttered view favored by technical analysts who prefer to focus on price levels rather than visual patterns.
# anyplot.ai
# ohlc-bar: OHLC Bar Chart
# Library: makie 0.21.9 | Julia 1.11.9
# Quality: 89/100 | Created: 2026-09-02
using CairoMakie
using Colors
using Dates
using Random
Random.seed!(42)
# --- Theme tokens -----------------------------------------------------------
const THEME = get(ENV, "ANYPLOT_THEME", "light")
const PAGE_BG = THEME == "light" ? colorant"#FAF8F1" : colorant"#1A1A17"
const INK = THEME == "light" ? colorant"#1A1A17" : colorant"#F0EFE8"
const INK_SOFT = THEME == "light" ? colorant"#4A4A44" : colorant"#B8B7B0"
const UP_COLOR = colorant"#009E73" # Imprint position 1 — bullish (close >= open)
const DOWN_COLOR = colorant"#AE3030" # Imprint semantic anchor — bearish (close < open)
# --- Data: 45 trading sessions of a fictional robotics stock (SLRA) ---------
start_date = Date(2024, 3, 1)
calendar_days = start_date:Day(1):(start_date + Day(90))
trading_dates = filter(d -> dayofweek(d) <= 5, collect(calendar_days))[1:45]
n_days = length(trading_dates)
open_prices = zeros(n_days)
high_prices = zeros(n_days)
low_prices = zeros(n_days)
close_prices = zeros(n_days)
price = 185.0
for i in 1:n_days
# Sessions 20-27 simulate an earnings-reaction stretch with wider ranges
vol_mult = (20 <= i <= 27) ? 2.6 : 1.0
open_prices[i] = price
close_prices[i] = max(price + randn() * 2.2 * vol_mult, 5.0)
high_prices[i] = max(open_prices[i], close_prices[i]) + abs(randn()) * 1.6 * vol_mult
low_prices[i] = min(open_prices[i], close_prices[i]) - abs(randn()) * 1.6 * vol_mult
global price = close_prices[i]
end
bar_up = close_prices .>= open_prices
bar_colors = [up ? UP_COLOR : DOWN_COLOR for up in bar_up]
peak_idx = argmax(high_prices)
trough_idx = argmin(low_prices)
# --- Plot ---------------------------------------------------------------
fig = Figure(
resolution = (1600, 900),
fontsize = 14,
backgroundcolor = PAGE_BG,
)
ax = Axis(
fig[1, 1];
title = "ohlc-bar · julia · makie · anyplot.ai",
titlesize = 25,
titlecolor = INK,
xlabel = "2024 Trading Sessions",
ylabel = "SLRA Share Price (USD)",
xlabelsize = 14,
ylabelsize = 14,
xlabelcolor = INK,
ylabelcolor = INK,
xticklabelsize = 11,
yticklabelsize = 12,
xticklabelcolor = INK_SOFT,
yticklabelcolor = INK_SOFT,
xticklabelrotation = pi / 6,
xtickcolor = INK_SOFT,
ytickcolor = INK_SOFT,
backgroundcolor = PAGE_BG,
topspinevisible = false,
rightspinevisible = false,
leftspinecolor = INK_SOFT,
bottomspinecolor = INK_SOFT,
xgridvisible = false,
ygridcolor = RGBAf(INK.r, INK.g, INK.b, 0.15),
)
tick_width = 0.32
xs = Float32.(1:n_days)
open_points = Point2f[]
close_points = Point2f[]
for i in 1:n_days
x = xs[i]
push!(open_points, Point2f(x - tick_width, open_prices[i]), Point2f(x, open_prices[i]))
push!(close_points, Point2f(x, close_prices[i]), Point2f(x + tick_width, close_prices[i]))
end
tick_colors = repeat(bar_colors, inner = 2)
rangebars!(ax, xs, low_prices, high_prices; color = bar_colors, linewidth = 2.5)
linesegments!(ax, open_points; color = tick_colors, linewidth = 2.5)
linesegments!(ax, close_points; color = tick_colors, linewidth = 2.5)
text!(
ax, xs[peak_idx], high_prices[peak_idx];
text = "Swing high", align = (:center, :bottom), offset = (0, 6),
fontsize = 11, color = INK_SOFT,
)
text!(
ax, xs[trough_idx], low_prices[trough_idx];
text = "Swing low", align = (:center, :top), offset = (0, -6),
fontsize = 11, color = INK_SOFT,
)
tick_step = 5
tick_positions = collect(1:tick_step:n_days)
ax.xticks = (Float32.(tick_positions), [Dates.format(trading_dates[i], "u dd") for i in tick_positions])
xlims!(ax, 0, n_days + 1)
ylims!(ax, minimum(low_prices) - 6, maximum(high_prices) + 6)
legend_elements = [
LineElement(color = UP_COLOR, linewidth = 2.5),
LineElement(color = DOWN_COLOR, linewidth = 2.5),
]
axislegend(
ax, legend_elements, ["Up (close ≥ open)", "Down (close < open)"];
position = :lt, framevisible = false, labelcolor = INK_SOFT, labelsize = 12,
)
# --- Save ---------------------------------------------------------------
save("plot-$(THEME).png", fig; px_per_unit = 2)
Runnable source as JSON, for any HTTP client: https://api.anyplot.ai/specs/ohlc-bar/makie/code. Any spec id and library id listed in llms-full.txt fit the same URL shape; every URL below is complete and callable.
{
"spec_id": "ohlc-bar",
"language": "julia",
"library": "makie",
"page": "https://anyplot.ai/ohlc-bar/julia/makie",
"hub": "https://anyplot.ai/ohlc-bar",
"code_json": "https://api.anyplot.ai/specs/ohlc-bar/makie/code",
"spec_json": "https://api.anyplot.ai/specs/ohlc-bar",
"render_light_png": "https://storage.googleapis.com/anyplot-images/plots/ohlc-bar/julia/makie/plot-light.png",
"render_dark_png": "https://storage.googleapis.com/anyplot-images/plots/ohlc-bar/julia/makie/plot-dark.png",
"quality_score": 89.0,
"license": "MIT",
"guide": "https://anyplot.ai/llms.txt"
}Part of OHLC Bar Chart on anyplot.ai.