10/01 - Vectors & Functions: Difference between revisions

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<math> f(t) = \int_{-\infty}^{\infty} f(u) \cdot \delta (t - u)\, du </math>
<math> f(t) = \int_{-\infty}^{\infty} f(u) \cdot \delta (t - u)\, du </math>


==Changing Basis Functions==
==Changing from one orthogonal Basis Functions to another==


*explain b_j
*explain b_j

Revision as of 13:43, 9 November 2008

Vectors & Functions

  • How to related the vector v to the sampling?

We could sample a continuous function every T seconds, creating a "bar graph".

f(t)=∑i=0N−1f(i⋅T)⋅p(t−i⋅T)

  • f(i⋅T) are the coefficients
  • p(t−i⋅T) are the basis functions, where p(t) is a rectangle 1 unit high and T units wide

In an effort to make this more exact, will will continue to shrink the rectangle down to the Dirac Delta function, δ

  • δ(x)={+∞,x=00,x≠0
  • ∫−∞∞δ(x)dx=1.

By using the Dirac Delta function the summation becomes an integral

f(t)=∫−∞∞f(u)⋅δ(t−u)du

Changing from one orthogonal Basis Functions to another

  • explain b_j