# Feature Descriptions

The *catch22* feature set provides open access to a powerful set of time-series analysis features that implemented efficiently for fast native feature computation in multiple coding languages. But the features (taken from the larger *hctsa* time-series feature set) can be hard to interpret :disappointed\_relieved:

The material in this chapter should help you to understand what each of these 22 features is doing, and point you to the relevant time-series theory that underpins it.

## *catch22* Feature Descriptions

Select the feature overview table for a high level description of each feature, or delve into detailed explanations and examples by exploring each of the 9 categories of time-series features included in *catch22*:

<table data-view="cards"><thead><tr><th></th><th align="center"></th><th></th><th data-hidden data-card-target data-type="content-ref"></th><th data-hidden data-card-cover data-type="files"></th></tr></thead><tbody><tr><td></td><td align="center"><strong>Feature overview table</strong></td><td></td><td><a href="/pages/Xul45GNpdBAJ3I0nN7Kt">/pages/Xul45GNpdBAJ3I0nN7Kt</a></td><td><a href="/files/5bamr7B2rENhzP6z0O3r">/files/5bamr7B2rENhzP6z0O3r</a></td></tr><tr><td></td><td align="center"><strong>Distribution shape</strong></td><td></td><td><a href="/pages/nctzQzagsdJOWpHWj9Cx">/pages/nctzQzagsdJOWpHWj9Cx</a></td><td><a href="/files/9KdZn0papm2HTTwNwaIr">/files/9KdZn0papm2HTTwNwaIr</a></td></tr><tr><td></td><td align="center"><strong>Extreme event timing</strong></td><td></td><td><a href="/pages/EomjKNr3aJAD0MXHwsm6">/pages/EomjKNr3aJAD0MXHwsm6</a></td><td><a href="/files/wnqdmgWEs9tTgvV08Xx4">/files/wnqdmgWEs9tTgvV08Xx4</a></td></tr><tr><td></td><td align="center"><strong>Linear autocorrelation structure</strong></td><td></td><td><a href="/pages/vlmWggwIfUzwmDZ4wS4V">/pages/vlmWggwIfUzwmDZ4wS4V</a></td><td><a href="/files/kM0DarBExw2eLKT7e0nP">/files/kM0DarBExw2eLKT7e0nP</a></td></tr><tr><td></td><td align="center"><strong>Nonlinear autocorrelation</strong></td><td></td><td><a href="/pages/wrrK3k9B55jjE1DP1m1D">/pages/wrrK3k9B55jjE1DP1m1D</a></td><td><a href="/files/XuWPjdco4778bt2cggL4">/files/XuWPjdco4778bt2cggL4</a></td></tr><tr><td></td><td align="center"><strong>Symbolic</strong></td><td></td><td><a href="/pages/TviXU4lDSIz49mOmu8rs">/pages/TviXU4lDSIz49mOmu8rs</a></td><td><a href="/files/LZRmSSo7VzN3Xt619lXU">/files/LZRmSSo7VzN3Xt619lXU</a></td></tr><tr><td></td><td align="center"><strong>Incremental differences</strong></td><td></td><td><a href="/pages/W4XP9ny3fZPpoVRxbPIX">/pages/W4XP9ny3fZPpoVRxbPIX</a></td><td><a href="/files/GObwsRdjgkZyf5wzCYPt">/files/GObwsRdjgkZyf5wzCYPt</a></td></tr><tr><td></td><td align="center"><strong>Simple forecasting</strong></td><td></td><td><a href="/pages/CUhw2Wl4c3y3VL7WMloO">/pages/CUhw2Wl4c3y3VL7WMloO</a></td><td><a href="/files/6HyML4BpxEZyCFWJG9KD">/files/6HyML4BpxEZyCFWJG9KD</a></td></tr><tr><td></td><td align="center"><strong>Self-affine scaling</strong></td><td></td><td><a href="/pages/zbKZQnJqhzVWXkQWEroK">/pages/zbKZQnJqhzVWXkQWEroK</a></td><td><a href="/files/oobHRAjezG1vZK9qBa16">/files/oobHRAjezG1vZK9qBa16</a></td></tr><tr><td></td><td align="center"><strong>Other</strong></td><td></td><td><a href="/pages/QZadAMHv1vJ39bk2jJH6">/pages/QZadAMHv1vJ39bk2jJH6</a></td><td><a href="/files/8E1Gy587RrTPpOuXbKF6">/files/8E1Gy587RrTPpOuXbKF6</a></td></tr></tbody></table>

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