stairs

Stairstep graph

Syntax

stairs(Y)

stairs(X,Y)

stairs(___,LineSpec)

stairs(___,Name,Value)

stairs(ax,___)

h = stairs(___)

[xb,yb] = stairs(___)

Description

stairs(Y) draws a stairstep graph of the elements in Y.

• If Y is a vector, then stairs draws one line.

• If Y is a matrix, then stairs draws one line per matrix column.

stairs(X,Y) plots the elements in Y at the locations specified by X. The inputs X and Y must be vectors or matrices of the same size. Additionally, X can be a row or column vector and Y must be a matrix with length(X) rows.

stairs(___,LineSpec) specifies a line style, marker symbol, and color. For example, ':*r' specifies a dotted red line with asterisk markers. Use this option with any of the input argument combinations in the previous syntaxes.

stairs(___,Name,Value) modifies the stairstep chart using one or more name-value pair arguments. For example, 'Marker','o','MarkerSize',8 specifies 8 point circle markers.

stairs(ax,___) plots into the axes specified by ax instead of into the current axes (gca). The option, ax, can precede any of the input argument combinations in the previous syntaxes.

h = stairs(___) returns one or more Stair objects. Use h to make changes to properties of a specific Stair object after it is created.

[xb,yb] = stairs(___) does not create a plot, but returns matrices xb and yb of the same size, such that plot(xb,yb) plots the stairstep graph.

Examples

Plot Single Data Series

Create a stairstep plot of sine evaluated at 40 equally spaced values between 0 and .

X = linspace(0,4*pi,40);
Y = sin(X);

figure
stairs(Y)

The length of Y automatically determines and generates the x-axis scale.

Plot Multiple Data Series

Create a stairstep plot of two cosine functions evaluated at 50 equally spaced values between 0 and .

X = linspace(0,4*pi,50)';
Y = [0.5*cos(X), 2*cos(X)];

figure
stairs(Y)

The number of rows in Y automatically determines and generates the x-axis scale.

Plot Single Data Series at Specified x-Values

Create a stairstep plot of a sine wave evaluated at equally spaced values between 0 and . Specify the set of x-values for the plot.

X = linspace(0,4*pi,40);
Y = sin(X);

figure
stairs(X,Y)

The entries in Y are plotted against the corresponding entries in X.

Plot Multiple Data Series at Specified x-Values

Create a stairstep plot of two cosine waves evaluated at equally spaced values between 0 and . Specify the set of x-values for the plot.

X = linspace(0,4*pi,50)';
Y = [0.5*cos(X), 2*cos(X)];

figure
stairs(X,Y)

The first vector input, X, determines the x-axis positions for both data series.

Plot Multiple Data Series at Unique Sets of x-Values

Create a stairstep plot of two sine waves evaluated at different values. Specify a unique set of x-values for plotting each data series.

x1 = linspace(0,2*pi)';
x2 = linspace(0,pi)';
X = [x1,x2];
Y = [sin(5*x1),exp(x2).*sin(5*x2)];

figure
stairs(X,Y)

Each column of X is plotted against the corresponding column of Y.

Specify Line Style, Marker Symbol and Color

Create a stairstep plot and set the line style to a dot-dashed line, the marker symbol to circles, and the color to red.

X = linspace(0,4*pi,20);
Y = sin(X);

figure
stairs(Y, '-.or')

Specify Additional Style Options

Create a stairstep plot and set the line width to 2, the marker symbols to diamonds, and the marker face color to cyan using Name,Value pair arguments.

X = linspace(0,4*pi,20);
Y = sin(X);

figure
stairs(Y,'LineWidth',2,'Marker','d','MarkerFaceColor','c')

Specify Axes for Stairstep Plots

Create a figure with two subplots and return the two axes handles, s(1) and s(2). Create a stairstep plot in each subplot by referring to the axes handles.

figure
s(1) = subplot(2,1,1);
s(2) = subplot(2,1,2);  

X = linspace(0,2*pi);
Y1 = 5*sin(X);
Y2 = sin(5*X);
stairs(s(1),X,Y1)
stairs(s(2),X,Y2)

Modify Stairstep Plot After Creation

Create a stairstep plot of two data series and return the two stair objects.

X = linspace(0,1,30)';
Y = [cos(10*X), exp(X).*sin(10*X)];
h = stairs(X,Y);

Use small circle markers for the first data series. Use magenta filled circles for the second series. Starting in R2014b, you can use dot notation to set properties. If you are using an earlier release, use the set function instead.

h(1).Marker = 'o';
h(1).MarkerSize = 4;
h(2).Marker = 'o';
h(2).MarkerFaceColor = 'm';

Create a Stairstep Plot using plot Function

Evaluate two cosine functions at 50 equally spaced values between 0 and and create a stairstep plot using plot.

X = linspace(0,4*pi,50)';
Y = [0.5*cos(X), 2*cos(X)];
[xb,yb] = stairs(X,Y);

stairs returns two matrices of the same size, xb and yb, but no plot.

Use plot to create the stairstep plot with xb and yb.

figure
plot(xb,yb)

Input Arguments

Y — y values

vector or matrix

y values, specified as a vector or matrix. When Y is a vector, stairs creates one stair object. When Y is a matrix, stairs draws one line per matrix column and creates a separate stair object for each column.

Data Types: single | double | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | categorical | datetime | duration

X — x values

vector or matrix

x values, specified as a vector or matrix. When Y is a vector, X must be a vector of the same size. When Y is a matrix, X must be a matrix of the same size, or a vector whose length equals the number of rows in Y.

Data Types: single | double | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | categorical | datetime | duration

LineSpec — Line style, marker symbol, and color

character vector | string

Line style, marker symbol, and color, specified as a character vector or string. For more information on line style, marker symbol, and color options see LineSpec.

Example: ':*r'

ax — Axes object

Axes object

Axes object. If you do not specify the axes, then stairs plots into the current axes.

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.

Example: 'Marker','s','MarkerFaceColor','red' plots the stairstep graph with red square markers.

The properties listed here are only a subset. For a complete list, see Stair Properties.

'LineStyle' — Line style

'-' (default) | '--' | ':' | '-.' | 'none'

Line style, specified as one of the options listed in this table.

Line Style	Description	Resulting Line
'-'	Solid line
'--'	Dashed line
':'	Dotted line
'-.'	Dash-dotted line
'none'	No line	No line

'LineWidth' — Line width

0.5 (default) | positive value

Line width, specified as a positive value in points. If the line has markers, then the line width also affects the marker edges.

Example: 0.75

'Color' — Line color

[0 0.4470 0.7410] (default) | RGB triplet | 'r' | 'g' | 'b' | ...

Line color, specified as an RGB triplet or one of the color options listed in the table.

For a custom color, specify an RGB triplet. 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]. Alternatively, you can specify some common colors by name. This table lists the long and short color name options and the equivalent RGB triplet values.

Option	Description	Equivalent RGB Triplet
'red' or 'r'	Red	[1 0 0]
'green' or 'g'	Green	[0 1 0]
'blue' or 'b'	Blue	[0 0 1]
'yellow' or 'y'	Yellow	[1 1 0]
'magenta' or 'm'	Magenta	[1 0 1]
'cyan' or 'c'	Cyan	[0 1 1]
'white' or 'w'	White	[1 1 1]
'black' or 'k'	Black	[0 0 0]
'none'	No color	Not applicable

Example: 'blue'

Example: [0 0 1]

'Marker' — Marker symbol

'none' (default) | 'o' | '+' | '*' | '.' | ...

Marker symbol, specified as one of the values listed in this table. By default, the object does not display markers. Specifying a marker symbol adds markers at each data point or vertex.

Value	Description
'o'	Circle
'+'	Plus sign
'*'	Asterisk
'.'	Point
'x'	Cross
'square' or 's'	Square
'diamond' or 'd'	Diamond
'^'	Upward-pointing triangle
'v'	Downward-pointing triangle
'>'	Right-pointing triangle
'<'	Left-pointing triangle
'pentagram' or 'p'	Five-pointed star (pentagram)
'hexagram' or 'h'	Six-pointed star (hexagram)
'none'	No markers

'MarkerSize' — Marker size

6 (default) | positive value

Marker size, specified as a positive value in points.

Example: 10

'MarkerEdgeColor' — Marker outline color

'auto' (default) | RGB triplet | 'r' | 'g' | 'b' | ...

Marker outline color, specified as 'auto', an RGB triplet, or one of the color options listed in the table. The default value of 'auto' uses the same color as the Color property.

For a custom color, specify an RGB triplet. 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]. Alternatively, you can specify some common colors by name. This table lists the long and short color name options and the equivalent RGB triplet values.

Option	Description	Equivalent RGB Triplet
'red' or 'r'	Red	[1 0 0]
'green' or 'g'	Green	[0 1 0]
'blue' or 'b'	Blue	[0 0 1]
'yellow' or 'y'	Yellow	[1 1 0]
'magenta' or 'm'	Magenta	[1 0 1]
'cyan' or 'c'	Cyan	[0 1 1]
'white' or 'w'	White	[1 1 1]
'black' or 'k'	Black	[0 0 0]
'none'	No color	Not applicable

Example: [0.5 0.5 0.5]

Example: 'blue'

'MarkerFaceColor' — Marker fill color

'none' (default) | 'auto' | RGB triplet | 'r' | 'g' | 'b' | ...

Marker fill color, specified as 'auto', an RGB triplet, or one of the color options listed in the table. The 'auto' value uses the same color as the Color property for the axes.

For a custom color, specify an RGB triplet. 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]. Alternatively, you can specify some common colors by name. This table lists the long and short color name options and the equivalent RGB triplet values.

Option	Description	Equivalent RGB Triplet
'red' or 'r'	Red	[1 0 0]
'green' or 'g'	Green	[0 1 0]
'blue' or 'b'	Blue	[0 0 1]
'yellow' or 'y'	Yellow	[1 1 0]
'magenta' or 'm'	Magenta	[1 0 1]
'cyan' or 'c'	Cyan	[0 1 1]
'white' or 'w'	White	[1 1 1]
'black' or 'k'	Black	[0 0 0]
'none'	No color	Not applicable

Example: [0.3 0.2 0.1]

Example: 'green'

Output Arguments

h — Stair objects

Stair objects

Stair objects. These are unique identifiers, which you can use to query and modify the properties of a specific Stair object after it is created.

xb — x values for use with plot

vector or matrix

x values for use with plot, returned as a vector or matrix. xb contains the appropriate values such that plot(xb,yb) creates the stairstep graph.

yb — y values for use with plot

vector or matrix

y values for use with plot, returned as a vector or matrix. yb contains the appropriate values such that plot(xb,yb) creates the stairstep graph.

Extended Capabilities

GPU Arrays

Accelerate code by running on a graphics processing unit (GPU) using Parallel Computing Toolbox™.

Usage notes and limitations:

• This function accepts GPU arrays, but does not run on a GPU.

For more information, see Run MATLAB Functions on a GPU (Parallel Computing Toolbox).

Distributed Arrays

Partition large arrays across the combined memory of your cluster using Parallel Computing Toolbox™.

Usage notes and limitations:

• This function operates on distributed arrays, but executes in the client MATLAB^®.

For more information, see Run MATLAB Functions with Distributed Arrays (Parallel Computing Toolbox).