Difference between revisions of "Integers"

From timescalewiki
Jump to: navigation, search
Line 2: Line 2:
  
 
{| class="wikitable"
 
{| class="wikitable"
|+$\mathbb{T}=h\mathbb{Z}$
+
|+$\mathbb{T}=\mathbb{Z}$
 
|-
 
|-
 
|Generic element $t\in \mathbb{T}$:
 
|Generic element $t\in \mathbb{T}$:

Revision as of 17:54, 20 May 2014

The set $\mathbb{Z}=\{\ldots,-2,-1,0,1,2,\ldots\}$ of integers is a time scale.

$\mathbb{T}=\mathbb{Z}$
Generic element $t\in \mathbb{T}$: For some $n \in \mathbb{Z}, t =n$
Jump operator: $\sigma(t)=t+1$
Graininess operator: $\mu(t)=1$
$\Delta$-derivative: $f^{\Delta}(t)=f(t+1)-f(t)$
$\Delta$-integral: $\displaystyle\int_s^t f(\tau) \Delta \tau = \displaystyle\sum_{k=s}^{t-1} f(k)$
Exponential function: $\begin{array}{ll} e_p(t,s) &= \exp \left( \displaystyle\int_{s}^{t} \dfrac{1}{\mu(\tau)} \log(1 + p(\tau)) \Delta \tau \right) \\ &= \exp \left( \displaystyle\sum_{k=s}^{t-1} \log(1+p(k)) \right) \\ &= \displaystyle\prod_{k=s}^{t-1} \left( 1+p(k) \right) \\ \end{array}$