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v2.2

Polar Chart

Chart for visualizing data in a Polar coordinate system ( angle + amplitude ). It has various different types of series:

Polar ChartPolar Chart

Creating Polar Chart​

import lightningchart as lc

chart = lc.PolarChart(title='PolarChart', theme=lc.Themes.Light)

Chart Title​

Control title, text, style, position, and visibility of the chart.

# Set or update the chart title
chart.set_title("My Custom Title")

# Change title color
chart.set_title_color('#FF0000')

# Adjust title font (size, family, weight, style)
chart.set_title_font(size=18, family="Arial, sans-serif", weight="bold", style="italic")

# Set padding below the title
chart.set_title_margin(10)

# Rotate title by 45°
chart.set_title_rotation(45)

# Apply theme effect (e.g. drop shadow)
chart.set_title_effect(True)

# Hide title altogether
chart.hide_title()

Angle (Radial) Axis​

Retrieve the angular axis for custom ticks, divisions, etc.:

radial_axis = chart.get_radial_axis()
# How many angular divisions (ticks) around the circle:
radial_axis.set_division(8)

# Read back the current division count:
current = radial_axis.get_division()

# Choose clockwise vs counter-clockwise rotation:
radial_axis.set_clockwise(True)

# Rotate which angle sits at “north”:
radial_axis.set_north(0)

# Replace all tick labels with your own list:
radial_axis.set_tick_labels(['N','NE','E','SE','S','SW','W','NW'])

Tick Label Styling​

Control font, rotation, and padding of radial axis tick labels:

radial = chart.get_radial_axis()

# Compact labels with a bit of spacing
radial.style_tick_labels(size=10, weight='600', rotation=0, tick_padding=3, label_padding=2)

Space After Ticks​

# Add extra margin after the radial axis ticks
chart.get_radial_axis().set_margin_after_ticks(4)

Amplitude Axis Tick Strategy​

By default amplitude axes use a numeric tick strategy. You can override it on either axis:

# On the amplitude axis:
chart.get_amplitude_axis().set_tick_strategy(
    'DateTime', time_origin=0, utc=True
)

Tick Label Styling​

Control font, rotation, and padding of amplitude tick labels.

amp = chart.get_amplitude_axis()

# Show 1 decimal place with a 'dB' suffix:  "12.3 dB"
amp.set_tick_format(decimals=1, suffix='dB')

# Plain integers, no suffix
amp.set_tick_format(decimals=0, suffix=None)

Chart Background​

Customize chart background.

# Solid background color
chart.set_background_color('#D80A0A')

# Background border/stroke
chart.set_background_stroke(2, 'red')

Set padding​

# To set padding around the chart in pixels
chart.set_padding(left=10, top=15, right=20, bottom=25)

Disable/Enable animations​

# To disable or enable all animations of the Chart
chart.set_animations_enabled(True)

solve_nearest​

Polar charts and every polar series (Line, Point, Point Line, Area, Polygon, Heatmap) inherit solve_nearest, letting you inspect the data point closest to a client coordinate or to the last pointer position.

# Chart-level solve_nearest in interpolated mode.
hits = chart.solve_nearest(client_x=420, client_y=300, solve_mode='show-nearest-interpolated')
for entry in hits:
    print(entry.get('series'), entry.get('angle'), entry.get('amplitude'))

# Series-level query.
result = series.solve_nearest(client_x=400, client_y=300)
for entry in result:
    print(entry.get('angle'), entry.get('amplitude'))

# Polar Heatmap example
heatmap_hits = heatmap.solve_nearest(client_x=420, client_y=300)
for entry in heatmap_hits:
    print(entry.get('sector'), entry.get('annulus'), entry.get('intensity'))
  • Valid solve_mode values: 'show-nearest', 'show-nearest-interpolated', 'show-pointed', 'show-pointed-interpolated', 'show-all', 'show-all-interpolated'.
  • When client_x and client_y are omitted the chart resolves the last mouse position, which is handy for hover tooltips.
  • Returned dictionaries always include the detected series name, and depending on the series type include angle / amplitude (polar series) or sector, annulus, and intensity (polar heatmap). Colors are reported as rgba strings when available, enabling synchronized highlights or annotations.

Add TextBox​

Please see common TextBox section.

Cursors​

Please see common Cursors section.

Legend​

Please see common legend section.