10/01 - Vectors & Functions

Vectors & Functions

• How to related the vector v to the sampling?

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

$f(t)=\sum _{i=0}^{N-1}f(iT)\cdot p(t-iT)$

• $f(iT)$ are the coefficients
• $p(t-iT)$ 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, $\delta$

• $\delta (x)=\{\begin{array}{ll}+\mathrm{\infty },& x=0\\ 0,& x\ne 0\end{array}$
• $\underset{-\mathrm{\infty }}{\overset{\mathrm{\infty }}{\int }}\delta (x)dx=1.$

By using the Dirac Delta function the summation becomes an integral

$f(t)=\underset{-\mathrm{\infty }}{\overset{\mathrm{\infty }}{\int }}f(u)\cdot \delta (t-u)du$

Changing from one orthogonal Basis Functions to another

• explain b_j