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plotyy

(Not recommended) Create graph with two y-axes

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    plotyy is not recommended. Use yyaxis instead. For more information on updating your code, see Version History.

    Syntax

    plotyy(X1,Y1,X2,Y2)
    plotyy(X1,Y1,X2,Y2,f)
    plotyy(X1,Y1,X2,Y2,f1,f2)
    plotyy(ax,___)
    [a,p1,p2] = plotyy(___)

    Description

    plotyy(X1,Y1,X2,Y2) plots Y1 against X1 with y-axis labeling on the left and plots Y2 against X2 with y-axis labeling on the right.

    example

    plotyy(X1,Y1,X2,Y2,f) uses the specified plotting function to plot the data.

    plotyy(X1,Y1,X2,Y2,f1,f2) uses the plotting function f1 to plot Y1 against X1 and the plotting function f2 to plot Y2 against X2.

    example

    plotyy(ax,___) displays the left plot in the specified axes instead of the current axes. If ax is a vector, then plotyy uses the first axes object in the vector. Specify the axes as the first argument in any of the previous syntaxes.

    [a,p1,p2] = plotyy(___) returns the two axes objects in a and the two graphics objects in p1 and p2. a(1) is the left axes and a(2) is the right axes. Use a, p1, and p2 to modify the properties of the axes and plots after creating them.

    example

    Examples

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    Open Live Script

    Plot two data sets on one graph using two y-axes.

    x = 0:0.01:20;
y1 = 200*exp(-0.05*x).*sin(x);
y2 = 0.8*exp(-0.5*x).*sin(10*x);

figure
plotyy(x,y1,x,y2)

    Figure contains 2 axes objects. Axes object 1 contains an object of type line. Axes object 2 contains an object of type line.

    Open Live Script

    Plot two data sets using a graph with two y-axes. Add a title and axis labels.

    x = 0:0.01:20;
y1 = 200*exp(-0.05*x).*sin(x);
y2 = 0.8*exp(-0.5*x).*sin(10*x);

figure
[hAx,hLine1,hLine2] = plotyy(x,y1,x,y2);

title("Multiple Decay Rates")
xlabel("Time (\musec)")

ylabel(hAx(1),"Slow Decay") % left y-axis 
ylabel(hAx(2),"Fast Decay") % right y-axis

    Figure contains 2 axes objects. Axes object 1 with title Multiple Decay Rates, xlabel Time (\musec), ylabel Slow Decay contains an object of type line. Axes object 2 with ylabel Fast Decay contains an object of type line.

    Open Live Script

    Plot two data sets using a graph with two y-axes. Change the line styles.

    x = 0:0.01:20;
y1 = 200*exp(-0.05*x).*sin(x);
y2 = 0.8*exp(-0.5*x).*sin(10*x);

[hAx,hLine1,hLine2] = plotyy(x,y1,x,y2);
hLine1.LineStyle = "--";
hLine2.LineStyle = ":";

    Figure contains 2 axes objects. Axes object 1 contains an object of type line. Axes object 2 contains an object of type line.

    Open Live Script

    Plot two data sets using a graph with two y-axes. Use a line plot for the data associated with the left y-axes. Use a stem plot for the data associated with the right y-axes.

    x = 0:0.1:10;
y1 = 200*exp(-0.05*x).*sin(x);
y2 = 0.8*exp(-0.5*x).*sin(10*x);

figure 
plotyy(x,y1,x,y2,@plot,@stem)

    Figure contains 2 axes objects. Axes object 1 contains an object of type line. Axes object 2 contains an object of type stem.

    Open Live Script

    Plot three data sets using a graph with two y-axes. Plot one set of data associated with the left y-axis. Plot two sets of data associated with the right y-axis by using two-column matrices.

    x = linspace(0,10);
y1 = 200*exp(-0.05*x).*sin(x);
y2 = 0.8*exp(-0.5*x).*sin(10*x);
y3 = 0.2*exp(-0.5*x).*sin(10*x);

figure
[hAx,hLine1,hLine2] = plotyy(x,y1,[x',x'],[y2',y3']);

    Figure contains 2 axes objects. Axes object 1 contains an object of type line. Axes object 2 contains 2 objects of type line.

    Input Arguments

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    x-coordinates, specified as a scalar, vector, or matrix.

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

    y-coordinates, specified as a scalar, vector, or matrix.

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

    Plotting function used to plot the data, specified as a function handle or a character vector that is the name of a plotting function, for example, semilogx, semilogy, loglog, stem, or any MATLAB® function that accepts the syntax h = function(x,y).

    Example: plotyy(x1,y1,x2,y2,@loglog)

    Example: plotyy(x1,y1,x2,y2,'loglog')

    Target axes, specified as an Axes object. If you do not specify the axes, MATLAB plots the first set of data into the current axes or creates an Axes object if one does not exist.

    Output Arguments

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    Two axes, returned as an array of two Axes objects. a(1) is the left axes and a(2) is the right axes. Use a to modify the properties of the axes.

    Graphics object. Use p to modify the properties of the plot after creating it.

    Extended Capabilities

    Version History

    Introduced before R2006a

    collapse all

    R2016a: Not recommended

    plotyy is not recommended. Use yyaxis instead. There are no plans to remove plotyy.

    Starting in R2016a, use the yyaxis function to create charts with two y-axes. The yyaxis function has several advantages over the plotyy function.

    • Unlike plotyy, the yyaxis function creates one Axes object with two y-axes. plotyy creates two overlaid Axes objects that can get out of sync.

    • You can use yyaxis with any 2-D plotting function. plotyy is limited to working with plotting functions of the form function(x,y). It does not work with other plotting functions, such as errorbar.

    This table shows some typical usages of plotyy and how to update your code to use yyaxis instead.

    Not RecommendedRecommended
    plotyy(x1,y1,x2,y2)
    		 
    yyaxis left 
plot(x1,y1) 
yyaxis right 
plot(x2,y2)
    plotyy(x1,y1,x2,y2, ...
'function1','function2')
    		 
    yyaxis left 
function1(x1,y1) 
yyaxis right 
function2(x2,y2)

    See Also

    Functions

    Topics