pathwaycom/pathway · error · ValueError
Cannot provide both [predicate, max_gap] at the same time.
Error message
Cannot provide both [predicate, max_gap] at the same time.
What it means
Error "Cannot provide both [predicate, max_gap] at the same time." thrown in pathwaycom/pathway.
Source
Thrown at python/pathway/stdlib/temporal/_window.py:559
... pw.this._pw_window_start,
... pw.this._pw_window_end,
... min_t=pw.reducers.min(pw.this.t),
... max_v=pw.reducers.max(pw.this.v),
... count=pw.reducers.count(),
... )
>>> pw.debug.compute_and_print(result, include_id=False)
_pw_instance | _pw_window_start | _pw_window_end | min_t | max_v | count
0 | 1 | 2 | 1 | 10 | 2
0 | 4 | 4 | 4 | 3 | 1
0 | 8 | 10 | 8 | 8 | 3
1 | 1 | 2 | 1 | 16 | 2
"""
if predicate is None and max_gap is None:
raise ValueError(
"At least one of the parameters [predicate, max_gap] should be provided."
)
elif predicate is not None and max_gap is not None:
raise ValueError("Cannot provide both [predicate, max_gap] at the same time.")
return _SessionWindow(predicate=predicate, max_gap=max_gap)
@check_arg_types
@trace_user_frame
def sliding(
hop: int | float | datetime.timedelta,
duration: int | float | datetime.timedelta | None = None,
ratio: int | None = None,
origin: int | float | datetime.datetime | None = None,
) -> Window:
"""Allows grouping together elements within a window of a given length sliding
across ordered time-like data column according to a specified interval (hop)
starting from a given origin.
Note:
Usually used as an argument of `.windowby()`.
Exactly one of the arguments `hop` or `ratio` should be provided.View on GitHub (pinned to fa2f74a464)
Solutions
- Provide only one of predicate or max_gap, not both.
Example fix
pw.temporal.sessionby(max_gap=timedelta(minutes=5))
When it happens
Trigger: Thrown at python/pathway/stdlib/temporal/_window.py:559 when the library encounters an invalid state.
Common situations: See trigger scenarios.
AI-assisted analysis of pathwaycom/pathway@fa2f74a464 (2026-08-15).
Data as JSON: /api/errors/47467cfba8f1c229.
Report an issue: GitHub.