def __init__(
self,
group_by=None,
order_by=None,
preceding=None,
following=None,
how='rows',
):
if group_by is None:
group_by = []
if order_by is None:
order_by = []
self._group_by = util.promote_list(group_by)
self._order_by = []
for x in util.promote_list(order_by):
if isinstance(x, ir.SortExpr):
pass
elif isinstance(x, ir.Expr):
x = ops.SortKey(x).to_expr()
self._order_by.append(x)
self.preceding = _list_to_tuple(preceding)
self.following = _list_to_tuple(following)
self.how = how
self._validate_frame()
def __init__(self, group_by=None, order_by=None,
preceding=None, following=None):
if group_by is None:
group_by = []
if order_by is None:
order_by = []
self._group_by = util.promote_list(group_by)
self._order_by = util.promote_list(order_by)
self._order_by = [ops.SortKey(expr)
if isinstance(expr, ir.Expr)
else expr
for expr in self._order_by]
self.preceding = _list_to_tuple(preceding)
self.following = _list_to_tuple(following)
self._validate_frame()
def desc(expr):
"""
Create a sort key (when used in sort_by) by the passed array expression or
column name.
Parameters
----------
expr : array expression or string
Can be a column name in the table being sorted
Examples
--------
result = (self.table.group_by('g')
.size('count')
.sort_by(ibis.desc('count')))
"""
if not isinstance(expr, Expr):
return _ops.DeferredSortKey(expr, ascending=False)
else:
return _ops.SortKey(expr, ascending=False)
def __init__(
self,
group_by=None,
order_by=None,
preceding=None,
following=None,
max_lookback=None,
how='rows',
):
import ibis.expr.operations as ops
self._group_by = tuple(
toolz.unique(
promote_list([] if group_by is None else group_by),
key=lambda value: getattr(value, "_key", value),
))
_order_by = []
for expr in promote_list([] if order_by is None else order_by):
if isinstance(expr, ir.Expr) and not isinstance(expr, ir.SortExpr):
expr = ops.SortKey(expr).to_expr()
_order_by.append(expr)
self._order_by = tuple(
toolz.unique(_order_by,
key=lambda value: getattr(value, "_key", value)))
if isinstance(preceding, RowsWithMaxLookback):
# the offset interval is used as the 'preceding' value of a window
# while 'rows' is used to adjust the window created using offset
self.preceding = preceding.max_lookback
self.max_lookback = preceding.rows
else:
self.preceding = _sequence_to_tuple(preceding)
self.max_lookback = max_lookback
self.following = _sequence_to_tuple(following)
self.how = how
self._validate_frame()
def __init__(
self,
group_by=None,
order_by=None,
preceding=None,
following=None,
max_lookback=None,
how='rows',
):
import ibis.expr.operations as ops
if group_by is None:
group_by = []
if order_by is None:
order_by = []
self._group_by = util.promote_list(group_by)
self._order_by = []
for x in util.promote_list(order_by):
if isinstance(x, ir.SortExpr):
pass
elif isinstance(x, ir.Expr):
x = ops.SortKey(x).to_expr()
self._order_by.append(x)
if isinstance(preceding, RowsWithMaxLookback):
# the offset interval is used as the 'preceding' value of a window
# while 'rows' is used to adjust the window created using offset
self.preceding = preceding.max_lookback
self.max_lookback = preceding.rows
else:
self.preceding = _sequence_to_tuple(preceding)
self.max_lookback = max_lookback
self.following = _sequence_to_tuple(following)
self.how = how
self._validate_frame()
def asc(expr: ir.ColumnExpr | str) -> ir.SortExpr | ops.DeferredSortKey:
"""Create a ascending sort key from `asc` or column name.
Parameters
----------
expr
The expression or column name to use for sorting
Examples
--------
>>> import ibis
>>> t = ibis.table([('g', 'string')])
>>> result = t.group_by('g').size('count').sort_by(ibis.asc('count'))
Returns
-------
ops.DeferredSortKey
A deferred sort key
"""
if not isinstance(expr, Expr):
return ops.DeferredSortKey(expr)
else:
return ops.SortKey(expr).to_expr()
