Deriving input-output relationship

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    deriving Relationship
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Discussion Overview

The discussion revolves around deriving a mathematical relationship between dependent (output) and independent (input) variables based on a limited number of sample points. Participants explore methods for generalizing this relationship and the challenges involved in doing so.

Discussion Character

  • Exploratory, Technical explanation, Debate/contested

Main Points Raised

  • One participant asks how to derive a mathematical relation from known samples of dependent and independent variables.
  • Another participant suggests that knowledge of the functional form is necessary to extrapolate from a few points to a general relationship.
  • A participant reiterates the need for a general form to fit the data, mentioning that without a guess of the functional form, generalization is not feasible.
  • It is proposed that a polynomial of sufficiently high degree can fit the data, but this may not represent the desired relationship accurately.
  • A participant clarifies that they have specific vectors for x and y and seeks to generalize the relationship between them based on the given samples.

Areas of Agreement / Disagreement

Participants express differing views on the feasibility of deriving a general relationship from limited samples, with some emphasizing the necessity of knowing the functional form and others discussing polynomial fitting as a potential approach. The discussion remains unresolved regarding the best method to generalize the relationship.

Contextual Notes

Limitations include the dependence on the assumed functional form and the challenges of fitting a polynomial to a finite number of samples, which may not yield the intended relationship.

jayki
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hi frenz

i want to how to derive mathematical relation between dependent(output) and independent(input) variables when i know the relation between them at few samples.
cud someone help me out?
thanks in advance
 
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do you know anything about the functional form? even roughly how it should look? if not then there is no way to extrapolate from a few points to every point.
 
olgranpappy said:
do you know anything about the functional form? even roughly how it should look? if not then there is no way to extrapolate from a few points to every point.

as i told , i know the relation between them at few samples. but i want to generalise as a mathematical relation between them
 
jayki said:
as i told , i know the relation between them at few samples. but i want to generalise as a mathematical relation between them

As olgranpappy says, you can't in general... without at least having a guess to the general form. Given a finite number of samples, you can fit it to a polynomial of sufficiently high degree. However, that polynomial is probably not what you are looking for.

http://en.wikipedia.org/wiki/Curve_fitting
In addition, note the diagrams in
http://slack.net/~ant/bl-synth/3.nyquist.html
 
thanks for ur response dear frenz...but let me clear my question again. I have a vector(x) and a vector(y) with the value of x at few points and corresponding value of y. I want to generalize the relation between them with that given samples.
 

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