Files
manifoldbt/benchmarks/vs_vectorbt/engine_mbt.py
Exocet92andGitHub 6cae686283 bench: add a cost workload and a multi-asset one, and go to three repetitions (#10)
Two gaps a reader could name without running anything: costs appeared on one
workload out of four, and nothing in the suite was a portfolio.

Costs could not simply be switched on across the board, and the reason is
measured. On FractionOfEquity sizing a 5 bps fee puts the engines 1.3e-4 of
capital apart and 2 bps of slippage 2.1e-5, against a 1e-9 tolerance, while the
round-trip counts stay identical: the trading agrees, the cost arithmetic does
not, because one charges the fee on top of the notional and the other reserves
it out of cash first. In fixed units both land exactly, to 1e-15. So
`sma_cross_costs` carries a fee and slippage on the headline signal, sized in
units, and the price of that is visible rather than hidden: x48.0 against x50.6
at 100k bars.

`multi_asset` runs five independent series in one shared book. It is the
workload manifoldbt does worst on, and it is here for that reason: going from
one asset to five costs it 6.1x and vectorbt 1.4x, so the ratio falls from x36.7
to x8.8 at a million bars. Broadcasting a column per asset is close to free;
walking five books is not. A portfolio is also what people actually run, and a
suite that only measures where it wins is not evidence.

Both are capped where a materialised five-column simulation would stop measuring
the engine and start measuring the swap file, and `ema_rsi_fees` keeps the
ceiling it got for going bankrupt.

Repetitions go from two to three: the floor at which a median is a median rather
than the mean of two.
2026-08-20 18:45:05 +02:00

221 lines
8.5 KiB
Python

"""manifoldbt adapter.
Public API only. The timed region is exactly what a user writes:
``bt.run(strategy, config, store)`` plus reading the headline metrics off the
result. Building the store from the DataFrame happens once, before timing, and
is excluded on both sides (vectorbt is likewise handed arrays it does not have
to load).
Execution conventions, chosen to line up with vectorbt rather than to flatter
either engine (same conventions as the parity suite shipped with the library):
* ``signal_delay=0`` and ``execution_price="AtClose"`` -> a market signal fills
at the close of the signal bar, which is what ``from_signals`` does by default.
* ``warmup_bars=0`` -> the indicator's own NaN warmup is what suppresses early
signals, identically on both sides.
* ``FractionOfEquity`` sizing is taken at the signal-bar close, which for a
market entry equals the fill price, so vectorbt ``size_type="percent"`` is the
matching mode.
"""
from __future__ import annotations
import os
from typing import Any, Callable, Dict
import data as data_mod
import manifoldbt as bt
from manifoldbt.expr import col, lit, when
from manifoldbt.helpers import Interval, Slippage
from manifoldbt.indicators import close as close_px, ema, rsi, sma
from workloads import CAPITAL, WORKLOADS
NAME = "manifoldbt"
def probe() -> Dict[str, Any]:
return {"engine": NAME, "version": bt.__version__}
def _config(df, *, sizing: str, fee_bps: float, slippage_bps: float = 0.0,
universe=None) -> "bt.BacktestConfig":
last_ns = int(df["timestamp"].iloc[-1].value)
fees = (
bt.FeeConfig.zero()
if fee_bps == 0.0
else bt.FeeConfig(maker_fee_bps=fee_bps, taker_fee_bps=fee_bps)
)
return bt.BacktestConfig(
universe=universe or [1],
time_range_start=0,
# A day past the last bar: the range is inclusive of everything generated.
time_range_end=last_ns + 86_400_000_000_000,
bar_interval=Interval.minutes(1),
initial_capital=CAPITAL,
execution=bt.ExecutionConfig(
signal_delay=0,
execution_price="AtClose",
max_position_pct=1.0,
allow_short=False,
position_sizing_mode=sizing,
),
fees=fees,
slippage=(Slippage.none() if slippage_bps == 0.0
else Slippage.fixed_bps(slippage_bps)),
warmup_bars=0,
)
def _strategy(key: str):
p = WORKLOADS[key].params
if key in ("sma_cross", "sma_cross_metrics"):
return (
bt.Strategy.create(key)
.signal("fast", sma(close_px, p["fast"]))
.signal("slow", sma(close_px, p["slow"]))
.size(when(col("fast") > col("slow"), lit(p["alloc"]), lit(0.0)))
)
if key == "bracket_sl_tp":
return (
bt.Strategy.create("bracket_sl_tp")
.signal("fast", sma(close_px, p["fast"]))
.signal("slow", sma(close_px, p["slow"]))
.size(when(col("fast") > col("slow"), lit(p["alloc"]), lit(0.0)))
.stop_loss(pct=p["sl_pct"])
.take_profit(pct=p["tp_pct"])
)
if key in ("sma_cross_costs", "multi_asset"):
# The same crossover as the headline workload. What differs is the cost
# model and the number of symbols the config points at, neither of which
# is visible from the strategy: a universe is walked by the engine, not
# spelled out per asset, which is the whole point of the comparison.
return (
bt.Strategy.create(key)
.signal("fast", sma(close_px, p["fast"]))
.signal("slow", sma(close_px, p["slow"]))
.size(when(col("fast") > col("slow"), lit(p["units"]), lit(0.0)))
)
if key == "ema_rsi_fees":
entry = (
(col("fast") > col("slow"))
& (col("rsi") > lit(p["rsi_lo"]))
& (col("rsi") < lit(p["rsi_hi"]))
)
return (
bt.Strategy.create("ema_rsi_fees")
.signal("fast", ema(close_px, p["fast"]))
.signal("slow", ema(close_px, p["slow"]))
.signal("rsi", rsi(close_px, p["rsi_period"]))
.signal("entry", entry)
.size(when(col("entry"), lit(p["units"]), lit(0.0)))
)
raise KeyError(f"unknown workload {key!r}")
def prepare(key: str, df, workdir: str) -> Callable[[], Dict[str, Any]]:
"""Untimed setup; returns the closure the harness times."""
p = WORKLOADS[key].params
fee_bps = float(p.get("fee_bps", 0.0))
sizing = "Units" if "units" in p else "FractionOfEquity"
root = os.path.join(workdir, key)
os.makedirs(root, exist_ok=True)
data_root = os.path.join(root, "data")
metadata_db = os.path.join(root, "metadata.sqlite")
assets = int(p.get("assets", 1))
if assets > 1:
# The universe is derived from the same generator and the same base
# seed, so the first symbol is the single-asset series bit for bit and
# the whole set is reproducible from the digest already recorded.
frames = data_mod.make_universe(len(df), assets)
for symbol_id, frame in frames.items():
store = bt.import_dataframe(
frame, symbol="A%d" % symbol_id, symbol_id=symbol_id,
interval="1m", data_root=data_root, metadata_db=metadata_db)
universe = list(frames)
else:
store = bt.import_dataframe(
df, symbol="BENCH", symbol_id=1, interval="1m",
data_root=data_root, metadata_db=metadata_db)
universe = [1]
strategy = _strategy(key)
config = _config(df, sizing=sizing, fee_bps=fee_bps,
slippage_bps=float(p.get("slippage_bps", 0.0)),
universe=universe)
wants_metrics = bool(p.get("metrics"))
def run() -> Dict[str, Any]:
result = bt.run(strategy, config, store)
m = result.metrics
ts = m.get("trade_stats") or {}
out = {
"total_return": float(m["total_return"]),
"final_equity": CAPITAL * (1.0 + float(m["total_return"])),
"round_trips": int(ts.get("round_trips", 0)),
"fills": int(ts.get("total_trades", 0)),
"total_fees": float(ts.get("total_fees", 0.0)),
}
if wants_metrics:
# Already computed by run(): reading them costs nothing measurable,
# which is the whole point of the comparison.
out.update({
"max_drawdown": float(m["max_drawdown"]),
"sharpe": float(m["sharpe"]),
"sortino": float(m["sortino"]),
"volatility": float(m["volatility"]),
})
return out
return run
def diagnose(key: str, df, workdir: str) -> Dict[str, Any]:
"""Untimed measurement of *how much* a documented divergence actually bites.
For the bracket workload this counts the round-trips whose entry lands on the
same bar as the previous exit, which is precisely the population the other
engines handle differently: vectorbt takes the next bar, raptorbt does not
re-enter at all. Reporting the count turns "the engines differ" into a number
a reader can weigh, and it is the same population for both of them.
"""
if not any(note.status == "documented" for note in WORKLOADS[key].notes.values()):
return {}
p = WORKLOADS[key].params
root = os.path.join(workdir, key + "_diag")
os.makedirs(root, exist_ok=True)
store = bt.import_dataframe(
df, symbol="BENCH", symbol_id=1, interval="1m",
data_root=os.path.join(root, "data"),
metadata_db=os.path.join(root, "metadata.sqlite"),
)
result = bt.run(
_strategy(key),
_config(df, sizing="Units" if "units" in p else "FractionOfEquity",
fee_bps=float(p.get("fee_bps", 0.0)),
slippage_bps=float(p.get("slippage_bps", 0.0))),
store,
)
trades = result.trades_df()
ts = trades["execution_timestamp"].to_numpy()
# Fills alternate entry, exit, entry, exit ... An entry that shares a bar
# with the exit before it is one the other engine would defer by one bar.
entries, exits = ts[0::2], ts[1::2]
n = min(len(exits), len(entries) - 1)
same_bar = int((exits[:n] == entries[1 : n + 1]).sum()) if n > 0 else 0
stats = result.metrics.get("trade_stats") or {}
round_trips = int(stats.get("round_trips", 0))
return {
"reentries_on_exit_bar": same_bar,
"round_trips": round_trips,
"share_of_round_trips": (same_bar / round_trips) if round_trips else 0.0,
"sl_exits": int(stats.get("sl_exits", 0)),
"tp_exits": int(stats.get("tp_exits", 0)),
}