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my-python-backteat/ferro-ta-main/python/ferro_ta/analysis/resample.py
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2026-07-09 05:08:16 +08:00

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Python

"""
OHLCV bar aggregation utilities.
resample_ohlcv(open, high, low, close, volume, factor)
Aggregate every `factor` bars into one OHLCV bar.
open = first bar's open
high = max of highs
low = min of lows
close = last bar's close
volume = sum of volumes
resample_ohlcv_labels(n_bars, factor)
Return an integer label array of length n_bars where label[i] = i // factor.
Useful for aligning fine-bar signals with coarse-bar indicators.
align_to_coarse(coarse_values, factor, n_fine_bars)
Broadcast a coarse-bar array back to fine-bar length by repeating each value `factor` times.
Handles the case where n_fine_bars % factor != 0 (last group may be partial).
"""
import numpy as np
from numpy.typing import ArrayLike, NDArray
__all__ = ["resample_ohlcv", "resample_ohlcv_labels", "align_to_coarse"]
def resample_ohlcv(
open_: ArrayLike,
high: ArrayLike,
low: ArrayLike,
close: ArrayLike,
volume: ArrayLike,
factor: int,
) -> tuple[NDArray, NDArray, NDArray, NDArray, NDArray]:
"""Aggregate fine-bar OHLCV into coarser bars.
Parameters
----------
open_ : array-like
Fine-bar open prices.
high : array-like
Fine-bar high prices.
low : array-like
Fine-bar low prices.
close : array-like
Fine-bar close prices.
volume : array-like
Fine-bar volume.
factor : int
Number of fine bars per coarse bar (e.g. 5 for 1-min -> 5-min).
Returns
-------
(open, high, low, close, volume) arrays of length ceil(n / factor).
Only complete groups are returned — if n % factor != 0, trailing bars are dropped.
"""
if factor < 1:
raise ValueError(f"factor must be >= 1, got {factor}")
o = np.asarray(open_, dtype=np.float64)
h = np.asarray(high, dtype=np.float64)
low_arr = np.asarray(low, dtype=np.float64)
c = np.asarray(close, dtype=np.float64)
v = np.asarray(volume, dtype=np.float64)
n = len(o)
n_complete = (n // factor) * factor # truncate to complete bars
o = o[:n_complete].reshape(-1, factor)
h = h[:n_complete].reshape(-1, factor)
low_arr = low_arr[:n_complete].reshape(-1, factor)
c = c[:n_complete].reshape(-1, factor)
v = v[:n_complete].reshape(-1, factor)
return (
o[:, 0], # open = first bar's open
h.max(axis=1), # high = max of highs
low_arr.min(axis=1), # low = min of lows
c[:, -1], # close = last bar's close
v.sum(axis=1), # volume = sum of volumes
)
def resample_ohlcv_labels(n_bars: int, factor: int) -> NDArray:
"""Return coarse-bar index for each fine bar (i // factor).
Parameters
----------
n_bars : int
Number of fine-resolution bars.
factor : int
Number of fine bars per coarse bar.
Returns
-------
NDArray of int64, shape (n_bars,), where label[i] = i // factor.
"""
if factor < 1:
raise ValueError(f"factor must be >= 1, got {factor}")
return np.arange(n_bars, dtype=np.int64) // factor
def align_to_coarse(coarse_values: ArrayLike, factor: int, n_fine_bars: int) -> NDArray:
"""Broadcast coarse-bar array back to fine-bar resolution.
Each coarse value is repeated `factor` times. If n_fine_bars % factor != 0,
the last coarse value covers the partial group at the end.
Parameters
----------
coarse_values : array-like
Values at coarse resolution, shape (n_coarse,).
factor : int
Number of fine bars per coarse bar.
n_fine_bars : int
Total number of fine bars to produce.
Returns
-------
NDArray of shape (n_fine_bars,).
"""
if factor < 1:
raise ValueError(f"factor must be >= 1, got {factor}")
coarse = np.asarray(coarse_values, dtype=np.float64)
n_coarse = len(coarse)
# Build the full repeated array (may be longer than n_fine_bars if partial group exists)
repeated = np.repeat(coarse, factor)
# If repeated is shorter than n_fine_bars (shouldn't happen with correct n_coarse,
# but handle defensively), pad with last value
if len(repeated) < n_fine_bars:
pad = np.full(
n_fine_bars - len(repeated), coarse[-1] if n_coarse > 0 else np.nan
)
repeated = np.concatenate([repeated, pad])
return repeated[:n_fine_bars]