help with curve fitting

trying to fit the curve on my graph so that it is rounded not sharp. Thank you.

figure(2);

plot(q_0,'ko-','Linewidth',1.5)

hold on

plot(q_1,'rs-','Linewidth',1.5)

plot(q_2,'bd-','Linewidth',1.5)

plot(q_3,'gv-','Linewidth',1.5)

hold off

xlim([1 13])

fit

legend({'Q0','Q1','Q2','Q3'})

Answer 1

[Ameer Hamza]

If you don't have an equation of your dataset, then it will be simpler to use the following methods

spline()

rng(0)
x = 1:10; % x-values
y = rand(size(x)); % random y-values

xv = linspace(min(x), max(x), 100); % more points on x-axis to make a smooth curve
yv = spline(x, y, xv); % interpolation using spline

plot(x, y, 'ro-', xv, yv, 'b-')

pchip()

rng(0)
x = 1:10; % x-values
y = rand(size(x)); % random y-values

xv = linspace(min(x), max(x), 100); % more points on x-axis to make a smooth curve
yv = pchip(x, y, xv); % interpolation using pchip

plot(x, y, 'ro-', xv, yv, 'b-')

makima()

rng(0)
x = 1:10; % x-values
y = rand(size(x)); % random y-values

xv = linspace(min(x), max(x), 100); % more points on x-axis to make a smooth curve
yv = makima(x, y, xv); % interpolation using makima

plot(x, y, 'ro-', xv, yv, 'b-')

Answer 2

[David Hill]

Use fit() function