xline — Draw vertical reference lines on the current axes.

xline adds one or more vertical reference lines to the current axes. It accepts scalar or vector x-coordinates, MATLAB line specs, labels, and common line name/value styling such as Color, LineStyle, LineWidth, and DisplayName.

How xline works

• xline(x) adds a vertical reference line at each coordinate in x.
• Reference lines append to the current axes without replacing existing plot content.
• Line spans follow the active axes limits, including later xlim and ylim changes.
• The returned handle supports get and set for Value, Color, LineWidth, LineStyle, Label, LabelOrientation, DisplayName, and Visible.

Examples

Add a dashed threshold line

plot(1:10, rand(1, 10));
xline(5, '--r', 'Threshold');

Expected output:

% Adds a red dashed vertical reference line at x = 5

Add multiple reference lines

plot(1:10, rand(1, 10));
xline([2 5 8], ':');

Expected output:

% Adds three dotted vertical reference lines

Related Plotting functions

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