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Output: Generates the new column, which contains the rolling count of non-null values of the current row and the two three previous row values in the myNumber column.

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Output: Generates the new column, which contains the rolling count of non-nulls from 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.

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