Axis Lines

Axis lines are vertical or horizontal lines that span an entire axis.

ScottPlot.Plot myPlot = new();

myPlot.Add.Signal(Generate.Sin());
myPlot.Add.Signal(Generate.Cos());

myPlot.Add.VerticalLine(24);
myPlot.Add.HorizontalLine(0.73);

myPlot.SavePng("demo.png", 400, 300);

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Axis Line Label

Axis lines have labels that can be used to display arbitrary text on the axes they are attached to.

AxisLines.cs

ScottPlot.Plot myPlot = new();

myPlot.Add.Signal(Generate.Sin());
myPlot.Add.Signal(Generate.Cos());

// by default labels are drawn on the same side as the axis label

var axLine1 = myPlot.Add.VerticalLine(24);
axLine1.Text = "Line 1";

var axLine2 = myPlot.Add.HorizontalLine(0.75);
axLine2.Text = "Line 2";

// labels may be drawn on the side opposite of the axis label

var axLine3 = myPlot.Add.VerticalLine(37);
axLine3.Text = "Line 3";
axLine3.LabelOppositeAxis = true;

var axLine4 = myPlot.Add.HorizontalLine(-.75);
axLine4.Text = "Line 4";
axLine4.LabelOppositeAxis = true;

// extra padding on the right and top ensures labels have room
myPlot.Axes.Right.MinimumSize = 30;
myPlot.Axes.Top.MinimumSize = 30;

myPlot.SavePng("demo.png", 400, 300);

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Axis Line Label Positioning

Axis line labels can have custom positioning, including rotation and alignment.

AxisLines.cs

ScottPlot.Plot myPlot = new();

myPlot.Add.Signal(Generate.Sin());
myPlot.Add.Signal(Generate.Cos());

var axLine1 = myPlot.Add.VerticalLine(42);
axLine1.Text = "Line 1";
axLine1.LabelRotation = -90;
axLine1.LabelAlignment = Alignment.MiddleRight;

var axLine2 = myPlot.Add.HorizontalLine(0.75);
axLine2.Text = "Line 2";
axLine2.LabelRotation = 0;
axLine2.LabelAlignment = Alignment.MiddleRight;

var axLine3 = myPlot.Add.VerticalLine(20);
axLine3.Text = "Line 3";
axLine3.LabelRotation = -45;
axLine3.LabelAlignment = Alignment.UpperRight;

// extra padding on the bottom and left for the rotated labels
myPlot.Axes.Bottom.MinimumSize = 60;
myPlot.Axes.Left.MinimumSize = 60;

myPlot.SavePng("demo.png", 400, 300);

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Axis Line Style

Axis lines have extensive customization options.

AxisLines.cs

ScottPlot.Plot myPlot = new();

myPlot.Add.Signal(Generate.Sin());
myPlot.Add.Signal(Generate.Cos());

var vl1 = myPlot.Add.VerticalLine(24);
vl1.LineWidth = 3;
vl1.Color = Colors.Magenta;

var hl1 = myPlot.Add.HorizontalLine(0.75);
hl1.LineWidth = 2;
hl1.Color = Colors.Green;
hl1.LinePattern = LinePattern.Dashed;

var hl2 = myPlot.Add.HorizontalLine(-.23);
hl2.LineColor = Colors.Navy;
hl2.LineWidth = 5;
hl2.Text = "Hello";
hl2.LabelFontSize = 24;
hl2.LabelBackgroundColor = Colors.Blue;
hl2.LabelFontColor = Colors.Yellow;
hl2.LinePattern = LinePattern.DenselyDashed;

myPlot.SavePng("demo.png", 400, 300);

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Axis Line In Legend

Axis lines will be added to the legend if their Text property is set unless their ExcludeFromLegend property is true.

AxisLines.cs

ScottPlot.Plot myPlot = new();

myPlot.Add.Signal(Generate.Sin());
myPlot.Add.Signal(Generate.Cos());

var axLine1 = myPlot.Add.VerticalLine(24);
axLine1.Text = "Line 1";

var axLine2 = myPlot.Add.HorizontalLine(0.75);

var axLine3 = myPlot.Add.VerticalLine(37);
axLine3.Text = "Line 3";
axLine3.ExcludeFromLegend = true;

var axLine4 = myPlot.Add.HorizontalLine(0.25);
axLine4.Text = "Line 4";

var axLine5 = myPlot.Add.HorizontalLine(-.75);
axLine5.Text = "Line 5";
axLine5.ExcludeFromLegend = true;

myPlot.ShowLegend();

myPlot.SavePng("demo.png", 400, 300);

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Ignore When Autoscaling

Calling Plot.Axes.AutoScale() or middle-clicking the plot will set the axis limits to fit the data. By default the position of axis lines and spans are included in automatic axis limit calculations, but a flag can be set to ignore certain plottables when automatically scaling the plot.

AxisLines.cs

ScottPlot.Plot myPlot = new();

myPlot.Add.Signal(Generate.Sin(51));
myPlot.Add.Signal(Generate.Cos(51));

var hline = myPlot.Add.HorizontalLine(0.23);
hline.IsDraggable = true;
hline.EnableAutoscale = false;

var hSpan = myPlot.Add.HorizontalSpan(-10, 20);
hSpan.IsDraggable = true;
hSpan.EnableAutoscale = false;

myPlot.SavePng("demo.png", 400, 300);

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Axis Line with Limits

Axis lines extend infinitely in both directions by default, but upper and lower limits may be specified to limit the dimensions of axis lines.

AxisLines.cs

ScottPlot.Plot myPlot = new();

myPlot.Add.Signal(Generate.Sin());
myPlot.Add.Signal(Generate.Cos());

var vLine = myPlot.Add.VerticalLine(24);
vLine.Minimum = -.5;
vLine.Maximum = 0.5;

var hLine = myPlot.Add.HorizontalLine(0.73);
hLine.Minimum = 10;
hLine.Maximum = 40;

myPlot.SavePng("demo.png", 400, 300);

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