"""
Copyright (C) 2013-2018 Calliope contributors listed in AUTHORS.
Licensed under the Apache 2.0 License (see LICENSE file).
masks.py
~~~~~~~~
Functions to pick timesteps from data given certain criteria.
"""
import pandas as pd
from calliope.core.time import funcs
from calliope.core.util.dataset import split_loc_techs
from calliope import exceptions
def _get_array(data, var, tech, **kwargs):
subset = {'techs': tech}
if kwargs is not None:
subset.update({k: v for k, v in kwargs.items()})
unusable_dims = (
set(subset.keys())
.difference(["techs", "locs"])
.difference(data[var].dims)
)
if unusable_dims:
raise exceptions.ModelError(
'Attempting to mask time based on technology {}, '
'but dimension(s) {} do not exist for parameter {}'.format(
tech, unusable_dims, var.name)
)
arr = split_loc_techs(data[var].copy()).loc[subset]
arr = arr.mean(dim=[i for i in arr.dims if i is not 'timesteps']).to_pandas()
return arr
def zero(data, tech, var='resource', **kwargs):
"""
Returns timesteps where ``var`` for the technology ``tech`` is zero.
kwargs are additional dimensions to subset on, for example,
``locs=['location1', 'location2]``
"""
s = _get_array(data, var, tech, **kwargs)
return s[s == 0].index
def _concat_indices(indices):
return pd.concat([i.to_series() for i in indices]).sort_index().index
def _get_minmax_timestamps(series, length, n, how='max', padding=None):
# Get the max/min timestamps
group = series.groupby(pd.Grouper(freq=length)).mean()
timesteps = []
for _ in range(n):
if how == 'max':
ts = group.idxmax()
elif how == 'min':
ts = group.idxmin()
timesteps.append(ts)
group = group.drop(ts)
# Get range of timestamps including padding
full_timesteps = []
for ts in timesteps:
ts_end = ts + pd.Timedelta(length)
if padding is not None:
ts -= pd.Timedelta(padding)
ts_end += pd.Timedelta(padding)
ts_range = series[ts:ts_end].index[:-1]
full_timesteps.append(ts_range)
ts_index = _concat_indices(full_timesteps)
return ts_index
[docs]def extreme(data, tech, var='resource', how='max',
length='1D', n=1, groupby_length=None,
padding=None, normalize=True, **kwargs):
"""
Returns timesteps for period of ``length`` where ``var`` for the technology
``tech`` across the given list of ``locations`` is either minimal
or maximal.
Parameters
----------
data : xarray.Dataset
tech : str
Technology whose `var` to find extreme for.
var : str, optional
default 'resource'
how : str, optional
'max' (default) or 'min'.
length : str, optional
Defaults to '1D'.
n : int, optional
Number of periods of `length` to look for, default is 1.
groupby_length : str, optional
Group time series and return `n` periods of `length`
for each group.
padding : str, optional
Either Pandas frequency (e.g. '1D') or 'calendar_week'.
If Pandas frequency, symmetric padding is undertaken, either side of `length`
If 'calendar_week', padding is fit to the calendar week in which the
extreme day(s) are found.
normalize : bool, optional
If True (default), data is normalized
using :func:`~calliope.core.time.funcs.normalized_copy`.
kwargs : dict, optional
Dimensions of the selected var over which to index. Any remaining
dimensions will be flattened by mean
"""
if normalize:
# Only normalise the desired var as rest of data may contain
# non-numeric variables!
data_n = funcs.normalized_copy(data[var].to_dataset(name=var))
else:
data_n = data
arr = _get_array(data_n, var, tech, **kwargs)
return _extreme_with_padding(arr, how, length, n, groupby_length, padding)
[docs]def extreme_diff(data, tech0, tech1, var='resource', how='max',
length='1D', n=1, groupby_length=None,
padding=None, normalize=True, **kwargs):
"""
Returns timesteps for period of ``length`` where the diffence in extreme
value for ``var`` between technologies ``tech0`` and ``tech1`` is either a
minimum or a maximum.
Parameters
----------
data : xarray.Dataset
tech0 : str
First technology for which we find the extreme of `var`
tech1 : str
Second technology for which we find the extreme of `var`
var : str, optional
default 'resource'
how : str, optional
'max' (default) or 'min'.
length : str, optional
Defaults to '1D'.
n : int, optional
Number of periods of `length` to look for, default is 1.
groupby_length : str, optional
Group time series and return `n` periods of `length`
for each group.
padding : str, optional
Either Pandas frequency (e.g. '1D') or 'calendar_week'.
If Pandas frequency, symmetric padding is undertaken, either side of `length`
If 'calendar_week', padding is fit to the calendar week in which the
extreme day(s) are found.
normalize : bool, optional
If True (default), data is normalized
using :func:`~calliope.core.time.funcs.normalized_copy`.
kwargs : dict, optional
Dimensions of the selected var over which to index. Any remaining
dimensions will be flattened by mean
"""
if normalize:
# Only normalise the desired var as rest of data may contain
# non-numeric variables!
data_n = funcs.normalized_copy(data[var].to_dataset(name=var))
else:
data_n = data
arr0 = _get_array(data_n, var, tech0, **kwargs)
arr1 = _get_array(data_n, var, tech1, **kwargs)
arr = arr0 - arr1
return _extreme_with_padding(arr, how, length, n, groupby_length, padding)
def _extreme(arr, how='max',
length='1D', n=1, groupby_length=None,
padding=None):
if groupby_length:
groupby = pd.Grouper(freq=groupby_length)
group_indices = []
grouping = arr.groupby(groupby)
for k in grouping.groups.keys():
s = grouping.get_group(k)
group_indices.append(_get_minmax_timestamps(s, length, n, how, padding))
ts_index = _concat_indices(group_indices)
else:
ts_index = _get_minmax_timestamps(arr, length, n, how, padding)
return ts_index
def _extreme_with_padding(arr, how, length, n, groupby_length, padding):
if padding == 'calendar_week':
if n != 1 or length != '1D':
raise ValueError(
'calendar_week padding only supports n=1 and length=1D for now.'
)
result = _extreme(arr, how, length, n, groupby_length, padding=None)
# get week padding for each day in result
days = list(result.groupby(result.dayofyear).values())
weeks = pd.DatetimeIndex(days[0])
for d in days:
weeks = weeks.union(_calendar_week_padding(d, arr))
# concatenate the weeks into one index and drop possible duplicates
return pd.DatetimeIndex(weeks).drop_duplicates()
else:
return _extreme(arr, how, length, n, groupby_length, padding)
def _calendar_week_padding(day, arr):
"""
Given a day, returns the whole calendar week which contains that day
"""
days = len(day.day.unique())
if not days == 1:
raise ValueError(
'Only a single day at a time may be used for calendar_week padding, '
'but {} days were passed.'.format(days)
)
# Using day of week, figure out how many days before and after to get
# a complete week
days_before = 6 - day[0].dayofweek
days_after = 6 - days_before
# Turn it into a week
start_time = day[0] - pd.Timedelta('{}D'.format(days_before))
end_time = day[-1] + pd.Timedelta('{}D'.format(days_after))
before = arr[start_time:day[0]].index[:-1]
after = arr[day[-1]:end_time].index[1:]
result_week = before.append(day).append(after)
return result_week
