A general time scale is oven denoted by

Let t be a point in the time scale.

We then make the following definitions.
1. The forward jump operator is the closest point to t on the right.
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2. The backward jump operator is the closest point to t on the left.

3. The graininess is the distance from t to its closest point on the right.
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These definitions are illustrated in the following figure.
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4. The time scale is said to be right scattered at point t if
This is illustrated in the following figure.

5. The time scale is said to be left scattered at point t if

This is illustrated in the following figure.
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6. The time scale is said to be right continuous at point t if
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7. The time scale is said to be left continuous at point t if

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