MATLAB: The Plot not showing a line only the points

Question

I need to show the plot with continous line but it keep plotting only the points, I don't understand the reason .

% Numerical Method of Solving ODE \ Euler Method%

'Example (1)''dy/dx=-y'

dy = @(x,y)-y;

f = @(x)exp(-x);

x0 = 0;

xn = 1;

y = 1;

h = 0.1;

fprintf (' x \t\t y (Euler)\t y(Exact) \n') % data table header

for x = x0 : h : xn-h

y = y + dy(x,y)*h;

x = x + h;

hold on

plot(x,y,'or');

xlabel('X');

ylabel('Y-by Euler method');

hold on

y2 = f(x);

plot(x,y2,'ob')

hold off

fprintf ('%f \t %f\t %f\n',x,y,f(x));

end

Answer 1

At any one time your x and y are scalar. plot() only produces lines when there are at least two adjacent finite points in a single plot call.

You should store all the x and y values and do the plot all at once afterwards.