saccade_length_in#

pymovements.measure.reading.saccade_length_in(fixations: DataFrame) → DataFrame[source]#

Compute the saccade length at word entry (SL_in).

SL_in is the signed word distance between the current word and the previously fixated word at the moment of the very first fixation on the current word.

Parameters:

fixations (pl.DataFrame) – Fixation table containing at least trial, page, word_idx, is_first_fix, and prev_word_idx columns.

Returns:

DataFrame with columns trial, page, word_idx, and SL_in.

Return type:

pl.DataFrame