mirror of
https://github.com/wassname/pandas-ta.git
synced 2026-06-27 16:10:07 +08:00
James Sawyer
78 lines
2.1 KiB
Python
78 lines
2.1 KiB
Python
# -*- coding: utf-8 -*-
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from ..overlap.ema import ema
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from ..overlap.hma import hma
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from ..overlap.sma import sma
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from ..overlap.rma import rma
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from ..overlap.wma import wma
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from ..utils import get_offset, verify_series, zero
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def bias(close, length=None, mamode=None, offset=None, **kwargs):
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"""Indicator: Bias (BIAS)"""
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# Validate Arguments
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close = verify_series(close)
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length = int(length) if length and length > 0 else 26
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mamode = mamode.lower() if mamode else None
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offset = get_offset(offset)
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# Calculate Result
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if mamode is None or mamode == "sma":
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ma = sma(close, length=length, **kwargs)
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if mamode == "ema":
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ma = ema(close, length=length, **kwargs)
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if mamode == "hma":
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ma = hma(close, length=length, **kwargs)
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if mamode == "rma":
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ma = rma(close, length=length, **kwargs)
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if mamode == "wma":
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ma = wma(close, length=length, **kwargs)
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bias = (close / ma) - 1
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# Offset
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if offset != 0:
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bias = bias.shift(offset)
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# Handle fills
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if "fillna" in kwargs:
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bias.fillna(kwargs["fillna"], inplace=True)
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if "fill_method" in kwargs:
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bias.fillna(method=kwargs["fill_method"], inplace=True)
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# Name and Categorize it
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bias.name = f"BIAS_{ma.name}"
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bias.category = "momentum"
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return bias
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bias.__doc__ = """Bias (BIAS)
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Rate of change between the source and a moving average.
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Sources:
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Few internet resources on definitive definition.
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Request by Github user homily, issue #46
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Calculation:
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Default Inputs:
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length=26, MA='sma'
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BIAS = (close - MA(close, length)) / MA(close, length)
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= (close / MA(close, length)) - 1
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Args:
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close (pd.Series): Series of 'close's
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length (int): The period. Default: 26
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mamode (str): Options: 'ema', 'hma', 'rma', 'sma', 'wma'. Default: 'sma'
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drift (int): The short period. Default: 1
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offset (int): How many periods to offset the result. Default: 0
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Kwargs:
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fillna (value, optional): pd.DataFrame.fillna(value)
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fill_method (value, optional): Type of fill method
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Returns:
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pd.Series: New feature generated.
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"""
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