A "plot" progression of points following a round course

Hi there,

Basically, I have these points on a plot but the thing is that I need to have the progression's shape to be round and not looking like a conglomerate of connected lines. I need something like in this picture from excel:

My actual plot looks like this at the moment:

Here's the code that I used, the values in the vectors mustn't be modified.

beta=[0 0.2 0.4 0.6 0.8 1 1.2];
randr=[0 84.25 89.97 91.38 91.60 91.32 90.81];
randrl=[0 79.08 86.38 88.23 88.51 88.15 87.48];
randrc=[0 76.24 84.33 86.41 86.74 86.33 85.57];

plot(beta,randr,'-d');
hold on;
plot(beta,randrl,'-d');
plot(beta,randrc,'-d');
xlabel('β');
ylabel('U2[V]');
grid on;
ylim([0 100]);

Answer 1

[Bora Eryilmaz]

You can use a (cubic) spline for interpolation.

beta=[0 0.2 0.4 0.6 0.8 1 1.2];
randr=[0 84.25 89.97 91.38 91.60 91.32 90.81];
randrl=[0 79.08 86.38 88.23 88.51 88.15 87.48];
randrc=[0 76.24 84.33 86.41 86.74 86.33 85.57];

% Use cubic spline for interpolation
x = linspace(min(beta), max(beta), 100); % Create a finer grid of x-axis values.
r = spline(beta, randr, x); % Interpolate on the finer grid.
rl = spline(beta, randrl, x);
rc = spline(beta, randrc, x);

plot(x,r,'-');
hold on;
plot(x,rl,'-');
plot(x,rc,'-');

plot(beta,randr,'d');
plot(beta,randrl,'d');
plot(beta,randrc,'d');
xlabel('β');
ylabel('U2[V]');
grid on;
ylim([0 100]);

[fie.minion]

Thanks a lot! This is exactly what I wanted. Cheers! :)