Plotting graph using for loop in MATLAB

Question

I\'m trying to plot a simple graph using for loop as shown below

x=linspace(0,2*pi,100);
for i=1:numel(x)
    y=sin(x(i));
    plot(x(i),y)
    hold on
end
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Answer 1

Simple approach

If you want to draw a curve as you add data, try the following:

x = linspace(0,2 * pi, 100);
y = zeros(size(x));
for i=1:numel(x)
     y(i) = sin(x(i));
     plot(x(1:i), y(1:i), 'color', 'r')
     drawnow();
end

Be aware that the plot automatically tries to set x and y limits (curve is scaled to the plot window), to prevent that you have to manually set the x- and y-limits with xlimand ylim.

As Matt wrote in his answer, calling plot in each iteration is quite expensive (i.e. time consuming). Therefore I suggest using datasources:

Update graph using data sources

% Create a panel and axes object
h_panel = uipanel;
h_axes = axes( 'Parent', h_panel);

% Create data sources
x = linspace(0,2 * pi, 100);
y = zeros(size(x));

% Create graph object, in this case stairs 
% and bind the variables x and y as its data sources
h_stairs = stairs(h_axes, x, y, 'XDataSource', 'x', 'YDataSource', 'y');

for i=1:size(x)
    y(i) = sin(x(i));
    % Update the data of the stairs graph
    refreshdata(h_stairs); 
    drawnow();
end

The call to drawnow isn't neccessary in each iteration, it is only used to update the visuals, so you can see the changes directly.