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v2.2

Scrolling Heatmap

Scrolling heatmaps can be created with Heatmap Scrolling Grid Series, which has an API for pushing data in a scrolling manner (append new data on top of existing data).

Scrolling HeatmapScrolling Heatmap

Creating Scrolling Heatmap​

series = chart.add_heatmap_scrolling_grid_series(resolution=10000, scroll_dimension='columns')

Positioning and Pixel Configuration​

These methods allow you to define the spatial positioning of heatmap samples and control bilinear interpolation on each pixel.

Set Start Coordinate​

# Set the start coordinate to (0, 0)
series.set_start(x=0, y=0)

Set Step Between Samples​

# Set the step between samples to 10 in X and 5 in Y
series.set_step(x=10, y=5)

Set Pixel Interpolation​

# Enable smooth pixel interpolation:
series.set_pixel_interpolation(True)

Add Intensity Values​

Append new rows of intensity data to enable scrolling visualization. Older data scrolls out as new data is added.

# Append a new row to the scrolling heatmap
new_row = [0.1, 0.2, 0.3, 0.4, 0.5]
series.add_intensity_values([new_row])

Customizing Fill Coloring​

Set Palette Coloring​

import lightningchart as lc

# Create a palette that transitions from blue to red:

series.set_palette_coloring(
    steps=[
        {'value': 0, 'color': '#0000FF'},
        {'value': 50, 'color': 'red'}
    ],
    look_up_property='value',
    interpolate=True
)

# With formatted legend display:
series.set_palette_coloring(
    steps=[
        {'value': 0, 'color': '#0000FF'},
        {'value': 100, 'color': '#FF0000'},
    ],
    look_up_property='value',
    formatter_precision=2,           # Decimal places
    formatter_unit='mag',             # Unit suffix
    formatter_scale=1.5,              # Scale values
    formatter_type='scientific',      # 'standard', 'compact', 'engineering', 'scientific'
    formatter_operation='floor',      # 'none', 'round', 'ceil', 'floor'
)

Solid Fill Color​

import lightningchart as lc

# Set the heatmap fill to a light gray:
series.set_color('#D3D3D3')

Removing Color​

# Remove the fill color:
series.set_empty_color_fill()

Wireframe Configuration​

Set Wireframe Stroke​

import lightningchart as lc

# Set a wireframe with 2px thickness in black:
series.set_wireframe_stroke(thickness=2, color='black')

Hide Wireframe​

# Hide the heatmap wireframe:
series.hide_wireframe()

Data Cleaning​

Turns on automatic data cleaning, which can help manage memory by removing outdated or unused samples.

# Enable automatic data cleaning:
series.enable_data_cleaning(True)

Scrolling heatmap does not currently have a method to control maximum memory usage precisely. enable_data_cleaning effectively enables "lazy" data cleaning, which will prevent applications from running out of memory, but when this data cleaning exactly happens is not guaranteed.

Series Utility Methods​

This section works the same as for Line, to avoid duplication of guides, please refer to the section under Line

Legend​

Please see common legend section.

Examples​

Link to the examples