MATLAB: Legend with Error Bars

MATLAB

I have a plot that includes several lines with error bars and a legend. I want the legend to only show the different lines, but when I create the legend it also includes a label for the error bars. How do I remove the error bars from the legend?

Best Answer

If you add the "errorbar" after _y_ou add the “legend”, the “legend” will automatically update to include the new “errorbar” handle. There are two ways around this.

You can add the “errorbar” before you add the “legend”:

% code for Line_1 and Line_2

errorbar(x, y, y_lower, y_upper, '.')
legend({'Line_1','Line_2'}) % The legend will only annotate the two labels you provided

Alternatively, if you need to add the “errorbar” after you add the “legend”, you can set the “errorbar” handle to be invisible. This will prevent the “legend” from updating with the new “errorbar” handle:

% code for Line_1 and Line_2
legend({'Line_1','Line_2'})
errorbar(x, y, y_lower, y_upper, '.', 'HandleVisibility','off') % The errorbar handle is not visible, preventing the legend from updating

Related Solutions

MATLAB: Displaying names of multiple variables in a plot

Let us assume that you have following variables created in your workspace:

>> v1 = rand(10,1);

>> v2 = rand(10,1)+1;

>> v3 = rand(10,1)+2;

>> v4 = rand(10,1)+3;

>> v5 = rand(10,1)+4;

>> v6 = rand(10,1)+5;

>> v7 = rand(10,1)+6;

>> v8 = rand(10,1)+7;

>> v9 = rand(10,1)+8;

1. You can concatenate all the variables into a matrix and then you can plot them as you iterate over matrix of variables using "for" loop with "hold on" command. To accomplish that you can execute following code:

>> variables = [v1,v2,v3,v4,v5,v6,v7,v8,v9]; % This creates (10-by-9) matrix containing variables as individual columns. All the variables should have same number of values else MATLAB will throw an error.

>> for i = 1:9

>> plot(dates, variables(:,i)); % Variables are plotted column by column.

>> hold on;

>> end

>> varNames = {'y = IEI','y = IEF','y = SHY','y = TLH','y = TLT','y = TIP','y = AGZ','y = CIU','y = HYG'}; % Create a cell array of strings for legend

>> legend(varNames, 'Location', 'SouthWest'); % Provide the cell array as an argument to "legend" function. Number of entries in cell array should be same as number of variables.

>> xlabel('Date');

>> ylabel('Normalized Price');

>> title('Normalized Asset Prices and Benchmark');

>> datetick('x');

>> grid on;

>> hold off;

2. You can concatenate all the variables into a matrix and provide that matrix as input to the plot function which will plot the data for you. You do not have to use "hold on" command in this approach. To accomplish this you can execute:

>> plot(dates,variables); % Variables are plotted column by column.