xline
Vertical line with constant x-value
Syntax
Description
xline( creates a constant vertical line
at the specified x-value in the current axes. For example,
xvalue)xline(2) creates a line at x = 2.
xline(___, specifies
constant line properties using one or more name-value pair arguments. For a list of
properties, see ConstantLine Properties. Specify name-value pairs after all other input arguments.Name,Value)
xl = xline(___) returns the
ConstantLine object created. Use xl to modify or
query properties of the line after it is created.
Examples
Create Vertical Line
Create a vertical line at x = 3.
xline(3);
Specify Vertical Line Style and Color
Create a red dashed line at x = 5.
xline(5,'--r');
Create Vertical Line with Label
To create a line with a label, you must also specify the line style. The default line style is a solid line, '-'.
x = linspace(0,6,100); y = exp(x); plot(x,y) xline(4.5,'-',{'Acceptable','Limit'});
Specify Vertical Line Properties
Create a vertical dash-dot line with both a label and a display name for a legend.
y = [3187 2693 1771 1826 1958 3222 1645]; barh(y,'DisplayName','Daily Sales') xl = xline(2328,'-.','Average','DisplayName','Average Sales');
Adjust the vertical and horizontal alignment of the line, then display the legend.
xl.LabelVerticalAlignment = 'middle'; xl.LabelHorizontalAlignment = 'center'; legend('show');
Plot Vertical Line in Specific Axes
Call the tiledlayout function to create a 2-by-1 tiled chart layout. Call the nexttile function to create the axes objects ax1 and ax2. Then plot into each of the axes. Add a dotted vertical line and label to each plot by passing the axes to the xline function.
tiledlayout(2,1) ax1 =nexttile; x = linspace(0,2*pi,200); y1 = cos(x); plot(ax1,x,y1) ax2 = nexttile; x = linspace(0,2*pi,200); y2 = sin(x); plot(ax2,x,y2) xlcosine = xline(ax1,pi/2,':','cos(\pi/2)=0'); xlsine = xline(ax2,pi,':','sin(\pi)=0');
Input Arguments
xvalue — Location of vertical line
scalar
Location of the vertical line on the x-axis, specified as a
scalar. You can specify xvalue as a numeric, categorical,
datetime, or duration value. However, the type of value you specify
must match the data type for the values along the x-axis.
Example: xline(12.4) plots the line at x = 12.4.
Example: xline(D(3)) plots the line at the value of the third
element in the array.
Example: xline(categorical({'orange'})) plots the line at the
category value 'orange'.
LineSpec — Line style, marker, and color
character vector | string
Line style, marker, and color, specified as a character vector or string containing symbols. The symbols can appear in any order. You do not need to specify all three characteristics (line style, marker, and color). For example, if you omit the line style and specify the marker, then the plot shows only the marker and no line.
Example: '--or' is a red dashed line with circle markers
| Line Style | Description |
|---|---|
- | Solid line |
-- | Dashed line |
: | Dotted line |
-. | Dash-dot line |
| Marker | Description |
|---|---|
'o' | Circle |
'+' | Plus sign |
'*' | Asterisk |
'.' | Point |
'x' | Cross |
'_' | Horizontal line |
'|' | Vertical line |
's' | Square |
'd' | Diamond |
'^' | Upward-pointing triangle |
'v' | Downward-pointing triangle |
'>' | Right-pointing triangle |
'<' | Left-pointing triangle |
'p' | Pentagram |
'h' | Hexagram |
| Color | Description |
|---|---|
| yellow |
| magenta |
| cyan |
| red |
| green |
| blue |
| white |
| black |
ax — Target axes
current axes (default) | Axes object
Target axes, specified as an Axes object. Use this argument if
you want xline to plot in axes other than the current axes.
label — Line label
'' (default) | character vector | cell array of character vectors | string array | numeric array
Line label, specified as a character vector, cell array of character vectors, string array, or numeric array. To create a multiline label, use a string array or a cell array of character vectors.
Example: xline(-pi/2,':','Lower Bound')
Example: xline(4,'-',{'first','second','third'})
Name-Value Pair Arguments
Specify optional
comma-separated pairs of Name,Value arguments. Name is
the argument name and Value is the corresponding value.
Name must appear inside quotes. You can specify several name and value
pair arguments in any order as
Name1,Value1,...,NameN,ValueN.
xline(5,'-','Max','LabelVerticalAlignment','middle')
specifies the vertical alignment of the label as 'middle'.Note
The properties listed here are only a subset. For a complete list, see ConstantLine Properties.
'Color' — Line color
[0.15 0.15 0.15] (default) | RGB triplet | hexadecimal color code | 'r' | 'g' | 'b' | ...
Line color, specified as an RGB triplet, a hexadecimal color code, a color name, or a short name.
For a custom color, specify an RGB triplet or a hexadecimal color code.
An RGB triplet is a three-element row vector whose elements specify the intensities of the red, green, and blue components of the color. The intensities must be in the range
[0,1]; for example,[0.4 0.6 0.7].A hexadecimal color code is a character vector or a string scalar that starts with a hash symbol (
#) followed by three or six hexadecimal digits, which can range from0toF. The values are not case sensitive. Thus, the color codes'#FF8800','#ff8800','#F80', and'#f80'are equivalent.
Alternatively, you can specify some common colors by name. This table lists the named color options, the equivalent RGB triplets, and hexadecimal color codes.
| Color Name | Short Name | RGB Triplet | Hexadecimal Color Code | Appearance |
|---|---|---|---|---|
'red' | 'r' | [1 0 0] | '#FF0000' |
|
'green' | 'g' | [0 1 0] | '#00FF00' |
|
'blue' | 'b' | [0 0 1] | '#0000FF' |
|
'cyan'
| 'c' | [0 1 1] | '#00FFFF' |
|
'magenta' | 'm' | [1 0 1] | '#FF00FF' |
|
'yellow' | 'y' | [1 1 0] | '#FFFF00' |
|
'black' | 'k' | [0 0 0] | '#000000' |
|
'white' | 'w' | [1 1 1] | '#FFFFFF' |
|
'none' | Not applicable | Not applicable | Not applicable | No color |
Here are the RGB triplets and hexadecimal color codes for the default colors MATLAB® uses in many types of plots.
| RGB Triplet | Hexadecimal Color Code | Appearance |
|---|---|---|
[0 0.4470 0.7410] | '#0072BD' |
|
[0.8500 0.3250 0.0980] | '#D95319' |
|
[0.9290 0.6940 0.1250] | '#EDB120' |
|
[0.4940 0.1840 0.5560] | '#7E2F8E' |
|
[0.4660 0.6740 0.1880] | '#77AC30' |
|
[0.3010 0.7450 0.9330] | '#4DBEEE' |
|
[0.6350 0.0780 0.1840] | '#A2142F' |
|
Example: 'g'
Example: [0.6 0.2 0.5]
Example: '#D2F9A7'
'LineWidth' — Line width
0.5 (default) | positive value
Line width, specified as a positive value in points.
'LabelHorizontalAlignment' — Horizontal alignment of label
'right' (default) | 'left' | 'center'
Horizontal alignment of the label with respect to the line, specified as one of the options in the table.
| Option | Description | Example |
|---|---|---|
'right' | Right side of the line. |
|
'left' | Left side of the line. |
|
'center' | Center of the line. The label segments the line. |
|
'LabelVerticalAlignment' — Vertical alignment of label
'top' (default) | 'middle' | 'bottom'
Vertical alignment of the label with respect to the line, specified as one of the options in the table.
| Option | Description | Example |
|---|---|---|
'top' | Top of the line |
|
'middle' | Middle of the line |
|
'bottom' | Bottom of the line |
|
'LabelOrientation' — Label orientation
'aligned' (default) | 'horizontal'
Label orientation, specified as 'aligned' or
'horizontal'. Examples are shown in the table.
| Orientation | Description | Example |
|---|---|---|
'aligned' | Label has the same orientation as the line. |
|
'horizontal' | Label is horizontal, regardless of the line orientation. |
|
Algorithms
In a 3-D view of the axes, the constant line appears in the x-y plane at the midpoint of the z-axis limits. If the axes are rotated, then the constant line rotates accordingly.