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Output: Generates the new column, which contains the rolling standard deviation of the two three previous row values, the current row value, and the two rows after the current one in the myNumber column.     

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Integers representing the number of rows before or after the current one from which to compute the rolling function, including the current row. For example, if the first value is 5, the current row and the four five rows after before it are used in the computation. Negative values for k compute the rolling average from rows preceding the current one.

• rowBefore=10 generates the current row value only.
• rowBefore=-1  uses all rows preceding the current one.
• If rowsAfter is not specified, then the value 0 is applied.
• If a group parameter is applied, then these parameter values should be no more than the maximum number of rows in the groups.

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