# Rolling The rolling function has the following syntax: **`rolling(, , , , min_periods = 2)`**

Parameter	Description	Value	Mandatory
Variable	Represents the measurements of a sensor as a time series of data points that vary over time. Also known as "dots", it is identified by a variable label.	Variable label	YES
Aggregation method	Computes the elements of a time series to return a single summary value.	mean, sum, min, max, count	YES
Type of range	Indicates whether a date range or a fixed number of elements is used to sample the time series.	window or values	YES
Range	The time window in which the function is computed. Note: Set the selected range for a "window" so it evenly divides the next range. For example, if you use minutes ("T"), the number n must evenly divide an hour ("H"). Available minute values are 1, 2, 3, 4, 5, 6, 10, 12, 15, 20, and 30. Other values may produce unexpected results. The same applies to other ranges.	Available data ranges: This is a positive integer that represents the number of observations used for each window, or a time range specified as follows: "nT": Every n minutes "nH": Every n hours "nD": Every n days	YES
Min periods	Number of values needed to calculate the rolling aggregation. By default, it is set to 2, which is the minimum required.	`min_periods = n`, where n is a positive integer.	NO

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