Any Curve Fitting Technique to Draw Curve

Dear All,

Firstly Thank you all experts, specially ImageAnalyst and KSSV (Siva Srinivas sir), really you people taught me a lot.

I have another small problem, I want to draw the approximate curve from (0,0) to (1,1), which should satisfy all points.The exponential curve should be like -----blue dash as shown in the figure.

How Matlab do that to draw the approximate blue line.

Any idea please.!

Answer 1

[John D'Errico]

This is a basic curvefitting problem. So use the curvefitting toolbox. But you need to choose a model. There is a lot of conflicting information here.

MUST the curve pass through all the points? You say it must "satisfy all points". That implies interpolation.

You talk about an approximate curve, which would belie the idea of interpolation.

Would the model be an exponential one, yet the curve is supposed to pass through (0,0) and (1,1)?

Again, the curve fitting toolbox may be a good choice for you. You still need to decide on a model to use that toolbox. At least, you need to tell people what is important about this curve.

So another option would be my SLM toolbox (which does call the optimization toolbox internally.) SLM can allow you to specify a curve fit to a set of points, but you can add information about the shape of that curve. You can require the curve to pass through (0,0) and (1,1), that it be monotone decreasing, but still have a negative second derivative everywhere (concave down), etc.