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TrickyDicky
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What is the minimum number of parameters needed to uniquely specify a point in a curved line?
Ben Niehoff said:One?
What are you trying to get at?
micromass said:A circle can be described as (cos(t),sin(t)). So it requires only one parameter, namely t...
micromass said:Well, to describe a point in [itex]\mathbb{R}^2[/itex], you'll need two values. So to describe a curve you'll need 2 coordinates. If that's what you're getting at.
TrickyDicky said:Basically what I was thinking is that for every curved manifold of a given dimension (one in the case of the circle), one needs n+1 coordinates to describe it in terms of the Euclidean embedding space, right?
You are right of course, I wasn't very precise, thanks for the reference.micromass said:This is certainly not true in general. It happens to be true for 1-dimensional manifolds though.
Take the Klein bottle for example, this has dimension 2, but one needs 4 coordinates to describe it, i.e. it can only be embedded in [itex]\mathbb{R}^4[/itex].
In general, take a look at the Whitney embedding theorem http://en.wikipedia.org/wiki/Whitney_embedding_theorem
which states that every smooth n-dimensional manifold can be embedded in [itex]\mathbb{R}^{2n}[/itex]. One cannot do better in general, although in some specific cases we can.
TrickyDicky said:What is the minimum number of parameters needed to uniquely specify a point in a curved line?
Sure, I was mixing there parameters, coordinates and dimensions.chiro said:If a proper parametrization exists, then one if your object is a line, no matter how many dimensions that curve is embedded in.
Curve parametrization is the process of representing a curve in terms of a single parameter, usually denoted by t. This allows for the precise description and calculation of points on the curve.
Having a minimum number of parameters for unique point specification is important because it simplifies the representation of a curve and makes it easier to work with mathematically. It also ensures that there is one and only one point specified for each value of the parameter.
The minimum number of parameters for curve parametrization is determined by the degree of the curve, which is the highest power of the parameter t in the equation. For example, a degree 2 curve, also known as a quadratic curve, would have a minimum of 2 parameters for unique point specification.
Some common methods for curve parametrization include linear, quadratic, cubic, and polynomial parametrization. These methods use different equations and numbers of parameters to represent curves of different degrees.
Yes, there are limitations to curve parametrization. Some curves, such as fractal curves, cannot be fully represented with a finite number of parameters. Additionally, some curves may require a higher number of parameters for unique point specification in order to accurately represent their shape.