xline — Draw vertical reference lines on current or specified axes with MATLAB-compatible styling forms.
xline adds one or more vertical reference lines with optional labels, line specs, and name-value styling, following MATLAB-compatible plotting behavior.
Syntax
h = xline(x)
h = xline(x, styleOrLabel)
h = xline(x, LineSpec, label)
h = xline(x, Name, Value, ...)Inputs
| Name | Type | Required | Default | Description |
|---|---|---|---|---|
x | NumericArray | Yes | — | X-coordinate scalar or numeric vector of vertical line positions. |
style_or_label | Any | No | — | LineSpec token (for example '--r') or label text. |
linespec | StyleSpec | Yes | — | Line style token (for example '--r'). |
label | StringScalar | Yes | — | Reference line label text. |
props | Any | Variadic | — | Style arguments and Name/Value pairs (Color, LineWidth, LineStyle, LabelOrientation, Visible). |
Returns
| Name | Type | Description |
|---|---|---|
h | NumericArray | Reference line handle scalar or row vector when multiple coordinates are provided. |
Errors
| Identifier | When | Message |
|---|---|---|
RunMat:xline:InvalidArgument | Coordinate input, style arguments, or Name/Value pairs are invalid. | xline: invalid argument |
RunMat:xline:Internal | Internal plotting state update fails. | xline: internal operation failed |
How xline works
xline(x)adds a vertical reference line at each coordinate inx.- Reference lines append to the current axes without replacing existing plot content.
- Line spans follow the active axes limits, including later
xlimandylimchanges. - The returned handle supports
getandsetforValue,Color,LineWidth,LineStyle,Label,LabelOrientation,DisplayName, andVisible.
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 = 5Add multiple reference lines
plot(1:10, rand(1, 10));
xline([2 5 8], ':');Expected output:
% Adds three dotted vertical reference linesRendered xline example
time = 0:0.25:12;
temperature = 62 + 1.4*time + 5*sin(0.55*time).*exp(-0.08*time);
plot(time, temperature, 'LineWidth', 2);
xline(6, '--r', 'Control change', 'LineWidth', 1.5);
title('Temperature During Test Run');
xlabel('Time (min)');
ylabel('Temperature (C)');
grid on;
Compare this result with other chart types in the MATLAB Plot Gallery.
Using xline with coding agents
Open a RunMat example with live inputs, then ask the agent to explain how xline changes the result.
Run a small xline example, explain the result, then change one input and compare the output.
Related Plotting functions
2D Charts
area · bar · errorbar · heatmap · hist · histogram · loglog · pie · plot · scatter · semilogx · semilogy · stairs · stem
Other
addpoints · ancestor · animatedline · axes · barh · cla · clf · colorcube · colororder · copyobj · daspect · datacursormode · dataTipTextRow · fcontour · figure · fill3 · findobj · fsurf · gobjects · groot · hgload · hgsave · hidden · histogram2 · hold · line · linkaxes · openfig · opengl · pan · parula · patch · plotmatrix · plotyy · polarhistogram · polarplot · polarscatter · print · quiver3 · ribbon · saveas · savefig · sphere · stackedplot · subtitle · suptitle · textscatter · textscatter3 · triplot · waitbar · wordcloud · xscale · xtickangle · xtickformat · xticklabels · xticks · yline · yscale · ytickangle · ytickformat · yticklabels · yticks · zoom
About RunMat
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