Curve Plotting

henry hill

Does anyone know how to plot a curve given 4 points? I'm doing this in matlab and using this curve I'm trying to predict the 5th point.

Any help is much appreciated, cheers.

Thomas_S_Hunterson

Freehand WIth a pencil???
Is it a quadratic graph??

dudara

you can create any kind of function that will fit four points and thus predict a 5th. however, to really do it, you should have a physical interpretation.

Give us a bit more info on the problem.

breadmonkey

Search the help section for "interp1". I think that can do it. I can't really explain it properly because I only used that function for the first time the other day.

breadmonkey

sean_keevey wrote:

Freehand WIth a pencil???
Is it a quadratic graph??

Come on man, we have a new thing called "technology"!:p

henry hill

dudara wrote:

Give us a bit more info on the problem.

Sorry for the lack of info. I'm doing a project on an autotram and need to be able to predict the the path of an object using a LIDAR range scanner. I'll try and give some sample input...

I have 4 points (representing the object @ sequential time intervals) with x representing the distance from the from the LIDAR and y the angle from it:
@time = 0 (2,2)
@time = 1 (4,6)
@time = 2 (5,6)
@time = 3 (4,7)

Q1. How do I represent these points as an equation and then as a curve?
Q2. How do I calculate the predicted 5th point @ time = 4? I believe i need to calculate the velocity, acceleration and jerk, but i'm unsure how to pull it all together?

Any help would be much appreciated. Thanks.

silverside

so can fit 4th order polynomial to 4 points, dunno how to do it in matlab but it's easy in general (think it might even be on LC syllabus)

Single Cell

@time=4 (2,11)