True Strength Index (TSI)

get_tsi(quotes, lookback_periods=25,smooth_periods=13, signal_periods=7)

Parameters

name	type	notes
`quotes`	Iterable[Quote]	Iterable of the Quote class or its sub-class. • See here for usage with pandas.DataFrame
`lookback_periods`	int, default 25	Number of periods (`N`) for the first EMA. Must be greater than 0.
`smooth_periods`	int, default 13	Number of periods (`M`) for the second smoothing. Must be greater than 0.
`signal_periods`	int, default 7	Number of periods (`S`) in the TSI moving average. Must be greater than or equal to 0.

Historical quotes requirements

You must have at least N+M+100 periods of quotes to cover the convergence periods. Since this uses a two EMA smoothing techniques, we recommend you use at least N+M+250 data points prior to the intended usage date for better precision.

quotes is an Iterable[Quote] collection of historical price quotes. It should have a consistent frequency (day, hour, minute, etc). See the Guide for more information.

Return

TSIResults[TSIResult]

This method returns a time series of all available indicator values for the quotes provided.
TSIResults is just a list of TSIResult.
It always returns the same number of elements as there are in the historical quotes.
It does not return a single incremental indicator value.
The first N+M-1 periods will have None values since there’s not enough data to calculate.
signal will be None for all periods if signal_periods=0.

⚞ Convergence warning: The first N+M+250 periods will have decreasing magnitude, convergence-related precision errors that can be as high as ~5% deviation in indicator values for earlier periods.

TSIResult

name	type	notes
`date`	datetime	Date
`tsi`	float, Optional	True Strength Index
`signal`	float, Optional	Signal line (EMA of TSI)

Utilities

See Utilities and Helpers for more information.

Example

from stock_indicators import indicators

# This method is NOT a part of the library.
quotes = get_historical_quotes("SPY")

# Calculate 20-period TSI
results = indicators.get_tsi(quotes, 25, 13, 7)

About True Strength Index (TSI)

Created by William Blau, the True Strength Index is a momentum oscillator that depicts trends in price changes. [Discuss] 💬