I sketched two horizontal line A and B and placed six point on each. Sketch a spline going through this points. Is it possible to make this points coincide with spline highest and lowest points? There is a way to do so but it is a circuitous root.

I sketched two horizontal line A and B and placed six point on each. Sketch a spline going through this points. Is it possible to make this points coincide with spline highest and lowest points? There is a way to do so but it is a circuitous root.

If you need a sine curve, you should use an equation-driven curve (or maybe a side view of a helix). B-spline won't yield a true sine curve.

The (orange) highlighted curve in 2D Sketch2 below uses

**Convert Entities**on 3D Helix/Spiral1 (blue) to create a spline.Sometimes, this method makes it easier to modify the curve after it is created or to create configurations that have varying curves. Fit spline could be used to get rid of the points where both ends of the spline are extended with straight lines.

Hi Maha Nadarasa

You should not fix spline points to horizontal lines. Use spline independent draw then tangent property.