Spline Series
Series type for visualizing a list of points (pair of X and Y coordinates), with an automatic polynomial interpolation that produces smooth curves.

Creating Spline series
series = chart.add_spline_series()
Adding Data
There are many different ways you can add data to a Spline series. The most basic way is to specify two lists of number values, one for X coordinates, and another for Y coordinates.
# Using x and y lists:
x_values = [0, 1, 2, 3]
y_values = [1, 3, 2, 4]
series.add(x_values, y_values)
Please refer to Adding Data to Charts section to see other available ways of adding data to a series.
Schema and Data Mapping
This section works the same as for Line, to avoid duplication of guides, please refer to the section under Line
Customizing Fill Coloring
Using Solid Point Color
import lightningchart as lc
series.set_point_color((255, 0, 0))
series.set_point_color('#FF0000')
series.set_point_color('red')
Using Solid /line Color
import lightningchart as lc
series.set_line_color((255, 0, 0))
series.set_line_color('#FF0000')
series.set_line_color('red')
Set Palette Coloring for Points
chart = lc.ChartXY(title='ChartXY', theme=lc.Themes.Light)
series = chart.add_spline_series()
x_values = [0, 1, 2, 3]
y_values = [2, 3, 5, 7]
series.add(x_values, y_values)
# Define a palette for the point coloring to interpolate between red, yellow and green:
series.set_palette_point_coloring(
steps=[
{'value': 2, 'color': '#FF0000', 'label': 'Min'},
{'value': 4, 'color': (255, 255, 0)},
{'value': 7, 'color': 'green', 'label': 'Max'},
],
look_up_property='y',
interpolate=True,
)
# With formatted legend display:
series.set_palette_point_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'
)

Set Palette Coloring for Lines
chart = lc.ChartXY(title='ChartXY', theme=lc.Themes.Light)
series = chart.add_spline_series()
x_values = [0, 1, 2, 3]
y_values = [2, 3, 5, 7]
series.add(x_values, y_values)
# Define a palette for the line stroke to interpolate between red and green:
series.set_palette_line_coloring(
steps=[
{'value': 2, 'color': '#FF0000'},
{'value': 7, 'color': 'green'},
],
look_up_property='y',
interpolate=True,
)

Customizing Line Appearance
Changing Line Thickness
series.set_line_thickness(5)
Changing Line Pattern
import lightningchart as lc
series.set_dashed(pattern="Dashed", thickness=3, color='#0000FF')
Available patterns include: "DashDotted", "Dashed", "DashedEqual", "DashedLoose", "Dotted", and "DottedDense".
Changing Point Shape
series.set_point_shape('circle')
Available patterns include: "arrow", "circle", "cross", "diamond", "minus", "plus", "square", "star" and "triangle".
Changing Point stroke style
series.set_point_stroke_style(style='solid', thickness=2, color="#ff0000")
Changing Point size
series.set_point_size(5)
Changing Point rotation
series.set_point_rotation(45)
Enabling or disabling individual point color attributes
series.set_individual_point_color_enabled(True)
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.