Hello Together, i dont know what polyval is doing here with the blue lines:

What i want is a line through all points (like the black one).

Code for it is at end.

- As you can see, the black line with polyval is plotted correct.
- The points yd1 for xd1 and yd2 for xd2 are plotted correct
- What is not plotted correct, is the polyval for xd1 and xd2 -> What have i done wrong here?

Thanks a lot!

`%Black line`

xml1 = [ -0.3, 0.4];yml1 = [-0.15, -0.15];xml2 = 0.4 + 0.7 * cos(0:pi/50:pi/2) ;yml2 = -0.85 +0.7 * sin(0:pi/50:pi/2);xml3 = [1.1, 1.1];yml3 = [-0.85, -1.15];load ('xdata310519.mat')%xd1 = 0 0.3906 0.7430 1.0227 1.2022 1.2641 1.2022

%yd1 = 0 -0.0619 -0.2414 -0.5211 -0.8735 -1.2641 -1.6547

%xd2 = 0 0.1943 0.3696 0.5087 0.5980 0.6288 0.5980

%yd2 = 0 -0.0308 -0.1201 -0.2592 -0.4345 -0.6288 -0.8231

grad = 5;p1 = polyfit( xd1, yd1, grad);p2 = polyfit( xd1, yd2, grad);f1 = polyval( p1, xd1);f2 = polyval( p2, xd2);hold on%Black lineplot(xml1, yml1, '--k');plot(xml2, yml2,'--k');plot(xml3, yml3, '--k');%points

plot(xd1, yd1,'s', xd2, yd2,'s');plot(xd1, f1,'b', xd2, f2,'b');

## Best Answer