# pandas.DataFrame.resample

`DataFrame.``resample`(rule, how=None, axis=0, fill_method=None, closed=None, label=None, convention='start', kind=None, loffset=None, limit=None, base=0, on=None, level=None)

  Resample time-series data.

  Convenience method for frequency conversion and resampling of time series. Object must have a datetime-like index (DatetimeIndex, PeriodIndex, or TimedeltaIndex), or pass datetime-like values to the on or level keyword.

  Parameters:

  rule : DateOffset, Timedelta or str

  > The offset string or object representing target conversion.

  how : str

  > Method for down/re-sampling, default to ‘mean’ for downsampling.

  > Deprecated since version 0.18.0: The new syntax is `.resample(...).mean()`, or `.resample(...).apply(<func>)`

  axis : {0 or ‘index’, 1 or ‘columns’}, default 0

  > Which axis to use for up- or down-sampling. For Series this will default to 0, i.e. along the rows. Must be DatetimeIndex, TimedeltaIndex or PeriodIndex.

  fill_method : str, default None

  > Filling method for upsampling.

  > Deprecated since version 0.18.0: The new syntax is `.resample(...).<func>()`, e.g. `.resample(...).pad()`

  closed : {‘right’, ‘left’}, default None

  > Which side of bin interval is closed. The default is ‘left’ for all frequency offsets except for ‘M’, ‘A’, ‘Q’, ‘BM’, ‘BA’, ‘BQ’, and ‘W’ which all have a default of ‘right’.

  label : {‘right’, ‘left’}, default None

  > Which bin edge label to label bucket with. The default is ‘left’ for all frequency offsets except for ‘M’, ‘A’, ‘Q’, ‘BM’, ‘BA’, ‘BQ’, and ‘W’ which all have a default of ‘right’.

  convention : {‘start’, ‘end’, ‘s’, ‘e’}, default ‘start’

  > For PeriodIndex only, controls whether to use the start or end of rule.

  kind : {‘timestamp’, ‘period’}, optional, default None

  > Pass ‘timestamp’ to convert the resulting index to a DateTimeIndex or ‘period’ to convert it to a PeriodIndex. By default the input representation is retained.

  loffset : timedelta, default None

  > Adjust the resampled time labels.

  limit : int, default None

  > Maximum size gap when reindexing with fill_method.

  > Deprecated since version 0.18.0.

  base : int, default 0

  > For frequencies that evenly subdivide 1 day, the “origin” of the aggregated intervals. For example, for ‘5min’ frequency, base could range from 0 through 4. Defaults to 0.

  on : str, optional

  > For a DataFrame, column to use instead of index for resampling. Column must be datetime-like.

  > New in version 0.19.0.

  level : str or int, optional

  > For a MultiIndex, level (name or number) to use for resampling. level must be datetime-like.

  > New in version 0.19.0.

  Returns: | Resampler object

  See also

  `groupby`
    Group by mapping, function, label, or list of labels.
  `Series.resample`
    Resample a Series.
  `DataFrame.resample`
    Resample a DataFrame.

  Notes

  See the user guide for more.

  To learn more about the offset strings, please see this link.

  Examples

  Start by creating a series with 9 one minute timestamps.

      >>> index = pd.date_range('1/1/2000', periods=9, freq='T')
      >>> series = pd.Series(range(9), index=index)
      >>> series
      2000-01-01 00:00:00    0
      2000-01-01 00:01:00    1
      2000-01-01 00:02:00    2
      2000-01-01 00:03:00    3
      2000-01-01 00:04:00    4
      2000-01-01 00:05:00    5
      2000-01-01 00:06:00    6
      2000-01-01 00:07:00    7
      2000-01-01 00:08:00    8
      Freq: T, dtype: int64

  Downsample the series into 3 minute bins and sum the values of the timestamps falling into a bin.

      >>> series.resample('3T').sum()
      2000-01-01 00:00:00     3
      2000-01-01 00:03:00    12
      2000-01-01 00:06:00    21
      Freq: 3T, dtype: int64

  Downsample the series into 3 minute bins as above, but label each bin using the right edge instead of the left. Please note that the value in the bucket used as the label is not included in the bucket, which it labels. For example, in the original series the bucket `2000-01-01 00:03:00` contains the value 3, but the summed value in the resampled bucket with the label `2000-01-01 00:03:00` does not include 3 (if it did, the summed value would be 6, not 3). To include this value close the right side of the bin interval as illustrated in the example below this one.

      >>> series.resample('3T', label='right').sum()
      2000-01-01 00:03:00     3
      2000-01-01 00:06:00    12
      2000-01-01 00:09:00    21
      Freq: 3T, dtype: int64

  Downsample the series into 3 minute bins as above, but close the right side of the bin interval.

      >>> series.resample('3T', label='right', closed='right').sum()
      2000-01-01 00:00:00     0
      2000-01-01 00:03:00     6
      2000-01-01 00:06:00    15
      2000-01-01 00:09:00    15
      Freq: 3T, dtype: int64

  Upsample the series into 30 second bins.

      >>> series.resample('30S').asfreq()[0:5]   # Select first 5 rows
      2000-01-01 00:00:00   0.0
      2000-01-01 00:00:30   NaN
      2000-01-01 00:01:00   1.0
      2000-01-01 00:01:30   NaN
      2000-01-01 00:02:00   2.0
      Freq: 30S, dtype: float64

  Upsample the series into 30 second bins and fill the `NaN` values using the `pad` method.

      >>> series.resample('30S').pad()[0:5]
      2000-01-01 00:00:00    0
      2000-01-01 00:00:30    0
      2000-01-01 00:01:00    1
      2000-01-01 00:01:30    1
      2000-01-01 00:02:00    2
      Freq: 30S, dtype: int64

  Upsample the series into 30 second bins and fill the `NaN` values using the `bfill` method.

      >>> series.resample('30S').bfill()[0:5]
      2000-01-01 00:00:00    0
      2000-01-01 00:00:30    1
      2000-01-01 00:01:00    1
      2000-01-01 00:01:30    2
      2000-01-01 00:02:00    2
      Freq: 30S, dtype: int64

  Pass a custom function via `apply`

      >>> def custom_resampler(array_like):
      ...     return np.sum(array_like) + 5
      ...
      >>> series.resample('3T').apply(custom_resampler)
      2000-01-01 00:00:00     8
      2000-01-01 00:03:00    17
      2000-01-01 00:06:00    26
      Freq: 3T, dtype: int64

  For a Series with a PeriodIndex, the keyword convention can be used to control whether to use the start or end of rule.

  Resample a year by quarter using ‘start’ convention. Values are assigned to the first quarter of the period.

      >>> s = pd.Series([1, 2], index=pd.period_range('2012-01-01',
      ...                                             freq='A',
      ...                                             periods=2))
      >>> s
      2012    1
      2013    2
      Freq: A-DEC, dtype: int64
      >>> s.resample('Q', convention='start').asfreq()
      2012Q1    1.0
      2012Q2    NaN
      2012Q3    NaN
      2012Q4    NaN
      2013Q1    2.0
      2013Q2    NaN
      2013Q3    NaN
      2013Q4    NaN
      Freq: Q-DEC, dtype: float64

  Resample quarters by month using ‘end’ convention. Values are assigned to the last month of the period.

      >>> q = pd.Series([1, 2, 3, 4], index=pd.period_range('2018-01-01',
      ...                                                   freq='Q',
      ...                                                   periods=4))
      >>> q
      2018Q1    1
      2018Q2    2
      2018Q3    3
      2018Q4    4
      Freq: Q-DEC, dtype: int64
      >>> q.resample('M', convention='end').asfreq()
      2018-03    1.0
      2018-04    NaN
      2018-05    NaN
      2018-06    2.0
      2018-07    NaN
      2018-08    NaN
      2018-09    3.0
      2018-10    NaN
      2018-11    NaN
      2018-12    4.0
      Freq: M, dtype: float64

  For DataFrame objects, the keyword on can be used to specify the column instead of the index for resampling.

      >>> d = dict({'price': [10, 11, 9, 13, 14, 18, 17, 19],
      ...           'volume': [50, 60, 40, 100, 50, 100, 40, 50]})
      >>> df = pd.DataFrame(d)
      >>> df['week_starting'] = pd.date_range('01/01/2018',
      ...                                     periods=8,
      ...                                     freq='W')
      >>> df
         price  volume week_starting
      0     10      50    2018-01-07
      1     11      60    2018-01-14
      2      9      40    2018-01-21
      3     13     100    2018-01-28
      4     14      50    2018-02-04
      5     18     100    2018-02-11
      6     17      40    2018-02-18
      7     19      50    2018-02-25
      >>> df.resample('M', on='week_starting').mean()
                     price  volume
      week_starting
      2018-01-31     10.75    62.5
      2018-02-28     17.00    60.0

  For a DataFrame with MultiIndex, the keyword level can be used to specify on which level the resampling needs to take place.

      >>> days = pd.date_range('1/1/2000', periods=4, freq='D')
      >>> d2 = dict({'price': [10, 11, 9, 13, 14, 18, 17, 19],
      ...            'volume': [50, 60, 40, 100, 50, 100, 40, 50]})
      >>> df2 = pd.DataFrame(d2,
      ...                    index=pd.MultiIndex.from_product([days,
      ...                                                     ['morning',
      ...                                                      'afternoon']]
      ...                                                     ))
      >>> df2
                            price  volume
      2000-01-01 morning       10      50
                 afternoon     11      60
      2000-01-02 morning        9      40
                 afternoon     13     100
      2000-01-03 morning       14      50
                 afternoon     18     100
      2000-01-04 morning       17      40
                 afternoon     19      50
      >>> df2.resample('D', level=0).sum()
                  price  volume
      2000-01-01     21     110
      2000-01-02     22     140
      2000-01-03     32     150
      2000-01-04     36      90

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