mars.dataframe.Series.diff#
- Series.diff(periods=1)#
First discrete difference of element. Calculates the difference of a Series element compared with another element in the Series (default is element in previous row).
- Parameters
periods (int, default 1) – Periods to shift for calculating difference, accepts negative values.
- Returns
First differences of the Series.
- Return type
See also
Series.pct_change
Percent change over given number of periods.
Series.shift
Shift index by desired number of periods with an optional time freq.
DataFrame.diff
First discrete difference of object.
Notes
For boolean dtypes, this uses
operator.xor()
rather thanoperator.sub()
.Examples
Difference with previous row
>>> import mars.dataframe as md >>> s = md.Series([1, 1, 2, 3, 5, 8]) >>> s.diff().execute() 0 NaN 1 0.0 2 1.0 3 1.0 4 2.0 5 3.0 dtype: float64
Difference with 3rd previous row
>>> s.diff(periods=3).execute() 0 NaN 1 NaN 2 NaN 3 2.0 4 4.0 5 6.0 dtype: float64
Difference with following row
>>> s.diff(periods=-1).execute() 0 0.0 1 -1.0 2 -1.0 3 -2.0 4 -3.0 5 NaN dtype: float64