stairs

Stairstep graph

• 

Syntax

stairs(Y)

stairs(X,Y)

stairs(___,LineSpec)

stairs(tbl,yvar)

stairs(tbl,xvar,yvar)

stairs(___,Name,Value)

stairs(ax,___)

h = stairs(___)

[xb,yb] = stairs(___)

Description

Vector and Matrix Data

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.

Table Data

stairs(tbl,yvar) plots the specified variable from the table against the row indices of the table. If the table is a timetable, the specified variable is plotted against the row times of the timetable. To plot one set of y-values, specify one variable for yvar. To plot multiple sets of y-values, specify multiple variables for yvar. (since R2022b)

stairs(tbl,xvar,yvar) plots the variables xvar and yvar from the table tbl. You can specify one or multiple variables for xvar and yvar. If both arguments specify multiple variables, they must specify the same number of variables. (since R2022b)

Additional Options

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.

This syntax does not support the table and table variable arguments.

Examples

Plot Single Data Series

Create a stairstep plot of sine evaluated at 40 equally spaced values between 0 and $$4\pi$$.

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 $$4\pi$$.

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 $$4\pi$$. 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 $$4\pi$$. 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')

Plot Data from a Table

Since R2022b

A convenient way to plot data from a table is to pass the table to the stairs function and specify the variables to plot.

Read the first 100 rows and 7 columns of weather.csv as a timetable tbl. Then display the first three rows of the table.

tbl = readtimetable("weather.csv","Range",[1 1 101 7]);
head(tbl,3)

            Time            WindDirection    WindSpeed    Humidity    Temperature    RainInchesPerMinute    CumulativeRainfall
    ____________________    _____________    _________    ________    ___________    ___________________    __________________

    25-Oct-2021 00:00:09         46               1          84          49.2                 0                     0         
    25-Oct-2021 00:01:09         45             1.6          84          49.2                 0                     0         
    25-Oct-2021 00:02:09         36             2.2          84          49.2                 0                     0         

Plot the Time variable on the x-axis and the CumulativeRainfall variable on the y-axis. Then use the axis padded command so that the line and the plot box do not overlap.

Return the Stair object as h. Notice that the axis labels match the variable names.

h = stairs(tbl,"Time","CumulativeRainfall");
axis padded

Change the color of the line to purple by setting the Color property.

h.Color = [0.5 0 0.8];

Plot Multiple Table Variables on One Axes

Since R2022b

Create vectors x, y1, and y2, and use them to create a table. Plot the y1 and y2 variables against the x variable. Use the axis padded command so that the line and the plot box do not overlap.

Add a legend, and notice that the legend labels match the variable names.

x = linspace(0,6,20);
y1 = cos(x);
y2 = sin(x);
tbl = table(x,y1,y2);
stairs(tbl,"x",["y1","y2"]);

% Pad x- and y-axes, and add legend
axis padded
legend

Alternatively, you can omit the x variable and plot the y1 and y2 variables against the row indices of the table.

stairs(tbl,["y1","y2"]);
axis padded
legend

Specify Axes for Stairstep Plots

Since R2019b

You can display a tiling of plots using the tiledlayout and nexttile functions. 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. Create separate stairstep plots in the axes by specifying the axes object as the first argument to stairs.

x = linspace(0,2*pi);
y1 = 5*sin(x);
y2 = sin(5*x);
tiledlayout(2,1)

% Top plot
ax1 = nexttile;
stairs(ax1,x,y1)

% Bottom plot
ax2 = nexttile;  
stairs(ax2,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. Use dot notation to set properties.

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 $$4\pi$$ 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, and color

string scalar | character vector

Line style, marker, and color, specified as a string scalar or character vector 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	Resulting Line
"-"	Solid line
"--"	Dashed line
":"	Dotted line
"-."	Dash-dotted line

Marker	Description	Resulting Marker
"o"	Circle
"+"	Plus sign
"*"	Asterisk
"."	Point
"x"	Cross
"_"	Horizontal line
"|"	Vertical line
"square"	Square
"diamond"	Diamond
"^"	Upward-pointing triangle
"v"	Downward-pointing triangle
">"	Right-pointing triangle
"<"	Left-pointing triangle
"pentagram"	Pentagram
"hexagram"	Hexagram

Color Name	Short Name	RGB Triplet	Appearance
"red"	"r"	[1 0 0]
"green"	"g"	[0 1 0]
"blue"	"b"	[0 0 1]
"cyan"	"c"	[0 1 1]
"magenta"	"m"	[1 0 1]
"yellow"	"y"	[1 1 0]
"black"	"k"	[0 0 0]
"white"	"w"	[1 1 1]

tbl — Source table

table | timetable

Source table containing the data to plot, specified as a table or a timetable.

yvar — Table variables containing y-coordinates

string array | character vector | cell array | pattern | numeric scalar or vector | logical vector | vartype()

Table variables containing the y-coordinates, specified using one of the indexing schemes from the table.

Indexing Scheme	Examples
Variable names: A string, character vector, or cell array. A pattern object.	"A" or 'A' — A variable named A ["A","B"] or {'A','B'} — Two variables named A and B "Var"+digitsPattern(1) — Variables named "Var" followed by a single digit
Variable index: An index number that refers to the location of a variable in the table. A vector of numbers. A logical vector. Typically, this vector is the same length as the number of variables, but you can omit trailing 0 or false values.	3 — The third variable from the table [2 3] — The second and third variables from the table [false false true] — The third variable
Variable type: A vartype subscript that selects variables of a specified type.	vartype("categorical") — All the variables containing categorical values

The table variables you specify can contain numeric, categorical, datetime, or duration values. If xvar and yvar both specify multiple variables, the number of variables must be the same.

Example: stairs(tbl,"x",["y1","y2"]) specifies the table variables named y1 and y2 for the y-coordinates.

Example: stairs(tbl,"x",2) specifies the second variable for the y-coordinates.

Example: stairs(tbl,"x",vartype("numeric")) specifies all numeric variables for the y-coordinates.

xvar — Table variables containing x-coordinates

string array | character vector | cell array | pattern | numeric scalar or vector | logical vector | vartype()

Table variables containing the x-coordinates, specified using one of the indexing schemes from the table.

Indexing Scheme	Examples
Variable names: A string, character vector, or cell array. A pattern object.	"A" or 'A' — A variable named A ["A","B"] or {'A','B'} — Two variables named A and B "Var"+digitsPattern(1) — Variables named "Var" followed by a single digit
Variable index: An index number that refers to the location of a variable in the table. A vector of numbers. A logical vector. Typically, this vector is the same length as the number of variables, but you can omit trailing 0 or false values.	3 — The third variable from the table [2 3] — The second and third variables from the table [false false true] — The third variable
Variable type: A vartype subscript that selects variables of a specified type.	vartype("categorical") — All the variables containing categorical values

The table variables you specify can contain numeric, categorical, datetime, or duration values. If xvar and yvar both specify multiple variables, the number of variables must be the same.

Example: stairs(tbl,["x1","x2"],"y") specifies the table variables named x1 and x2 for the x-coordinates.

Example: stairs(tbl,2,"y") specifies the second variable for the x-coordinates.

Example: stairs(tbl,vartype("numeric"),"y") specifies all numeric variables for the x-coordinates.

ax — Axes object

Axes object

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

Name-Value Arguments

Specify optional pairs of arguments as Name1=Value1,...,NameN=ValueN, where Name is the argument name and Value is the corresponding value. Name-value arguments must appear after other arguments, but the order of the pairs does not matter.

Before R2021a, use commas to separate each name and value, and enclose Name in quotes.

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, where 1 point = 1/72 of an inch. If the line has markers, then the line width also affects the marker edges.

The line width cannot be thinner than the width of a pixel. If you set the line width to a value that is less than the width of a pixel on your system, the line displays as one pixel wide.

Color — Line color

[0 0.4470 0.7410] (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 string scalar or character vector that starts with a hash symbol (#) followed by three or six hexadecimal digits, which can range from 0 to F. The values are not case sensitive. Therefore, 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: "blue"

Example: [0 0 1]

Example: "#0000FF"

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.

Marker	Description	Resulting Marker
"o"	Circle
"+"	Plus sign
"*"	Asterisk
"."	Point
"x"	Cross
"_"	Horizontal line
"|"	Vertical line
"square"	Square
"diamond"	Diamond
"^"	Upward-pointing triangle
"v"	Downward-pointing triangle
">"	Right-pointing triangle
"<"	Left-pointing triangle
"pentagram"	Pentagram
"hexagram"	Hexagram
"none"	No markers	Not applicable

MarkerSize — Marker size

6 (default) | positive value

Marker size, specified as a positive value in points, where 1 point = 1/72 of an inch.

MarkerEdgeColor — Marker outline color

"auto" (default) | RGB triplet | hexadecimal color code | "r" | "g" | "b" | ...

Marker outline color, specified as "auto", an RGB triplet, a hexadecimal color code, a color name, or a short name. The default value of "auto" uses the same color as the Color property.

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 string scalar or character vector that starts with a hash symbol (#) followed by three or six hexadecimal digits, which can range from 0 to F. The values are not case sensitive. Therefore, 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"

MarkerFaceColor — Marker fill color

"none" (default) | "auto" | RGB triplet | hexadecimal color code | "r" | "g" | "b" | ...

Marker fill color, specified as "auto", an RGB triplet, a hexadecimal color code, a color name, or a short name. The "auto" option uses the same color as the Color property of the parent axes. If you specify "auto" and the axes plot box is invisible, the marker fill color is the color of the figure.

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 string scalar or character vector that starts with a hash symbol (#) followed by three or six hexadecimal digits, which can range from 0 to F. The values are not case sensitive. Therefore, 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"

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).

Version History

Introduced before R2006a

R2022b: Pass tables directly to stairs

Create plots by passing a table to the stairs function followed by the variables you want to plot. When you specify your data as a table, the axis labels and the legend (if present) are automatically labeled using the table variable names.