Problem with using 'DisplayName' property in fplot()

Hello everbody,

I wrote a function to plot a limit value in a existing figure. You can see it below. This function works well without using 'DisplayName' in fplot().

If I want to use 'DisplayName' I have got the following error:

Error using plot

Error in color/linetype argument.

Error in fplot (line 154)

plot(xx,y,marker,'parent',cax)

Error in limits (line 48)

fplot(f, axes.XLim, 'DisplayName', 'Test')

Can someone help me to fix this problem.

Thank you in advance,

Lennart

function limits(fig, standard)
    %% Code
    axes = fig.CurrentAxes;
    axes.NextPlot = 'add';
    if strcmp(standard, 'ECE R10 10m QuasiPeak') 
        f1 = @(x) 32;
        f2 = @(x) 32 + 15.13 .* log10(x/75000000);
        f3 = @(x) 43;
    elseif strcmp(standard, 'ECE R10 10m Average')
        f1 = @(x) 22;
        f2 = @(x) 22 + 15.13 .* log10(x/75000000);
        f3 = @(x) 33;
    elseif strcmp(standard, 'ECE R10 3m QuasiPeak')
        f1 = @(x) 42;
        f2 = @(x) 42 + 15.13 .* log10(x/75000000) ;
        f3 = @(x) 53;
    elseif strcmp(standard, 'ECE R10 3m Average')
        f1 = @(x) 32;
        f2 = @(x) 32 + 15.13 .* log10(x/75000000) ;
        f3 = @(x) 43;
    elseif strcmp(standard, 'ECE R10 EUB QuasiPeak')
        f1 = @(x) 62 - 25.13 .* log10(x/3000000);
        f2 = @(x) 52 + 15.13 .* log10(x/75000000) ;
        f3 = @(x) 63;
    elseif strcmp(standard, 'ECE R10 EUB Average')
        f1 = @(x) 52 - 25.13 .* log10(x/3000000);
        f2 = @(x) 42 + 15.13 .* log10(x/75000000) ;
        f3 = @(x) 53;
    else 
        error('Dies ist kein vorhandener Grenzwert!')
    end
    f = @(x) f1(x).*((30000000 <= x) & (x <= 75000000)) + f2(x).*((75000000 < x) & (x < 400000000)) + f3(x).*((400000000 <= x) & (x < 1000000000));

    fplot(f, axes.XLim, 'DisplayName', 'Test')
end

[Robert U]

Problem seems not to be "DisplayName" property but the limits given by axes.XLim.

Kind regards,

Robert

[Lennart Reich]

But without axes.XLim I have got the same error.

Answer 1

[madhan ravi]

F = fplot(f);
set(F, 'DisplayName', 'Test')

[Walter Roberson]

Right. DisplayName is not an option that is accepted by fplot(). fplot() only accepts some color related and marker related and line style related options, together with some mesh options.

[Lennart Reich]

If I'm using it like you I have got the error:

Index exceeds matrix dimensions.

Error in fplot (line 56)

lims = args{2};

Error in limits (line 47)

F = fplot(f);

If I'm using it with axes.XLim():

F = fplot(f, axes.XLim);
set(F, 'DisplayName', 'Test');

I have got the error:

Error using matlab.graphics.Graphics/set

There is no DisplayName property on the Root class.

Error in limits (line 48)

set(F, 'DisplayName', 'Test');

[madhan ravi]

 which fplot -all % ?

Hope you didn’t mess the stock file.

[Lennart Reich]

@madhan ravi: I have got this as response:

C:\Program Files\MATLAB\R2015b\toolbox\matlab\specgraph\fplot.m

So I think this is right or?

@walter roberson: But why I can find it FunctionLine Properties. Besides they use 'LineWidth' in an example of the fplot function. This will give the same error.

[Walter Roberson]

Ah, notice they are using R2015b.

[Walter Roberson]

In R2015b,

[X,Y] = fplot(FUN,LIMS,...) returns X and Y such that Y = FUN(X). No plot is drawn on the screen.

So you have to do something like

curchild = get(axes,'Children');
fplot(f, axes.XLim);
newchild = get(axes, 'Children');
newline = setdiff(newchild, curchild);
set(newline, 'DisplayName', 'Test')

and at some point

legend show

[madhan ravi]

Thank you sir Walter!

[Lennart Reich]

Yeah this works fine. Thank you Walter.