Why is the length of smoothed data from filtfilt always double of the input?

1. What is the purpose of the filtfilt function in Matlab?
2. What does signal filtfilt do?
3. What is filtfilt Python?

What is the purpose of the filtfilt function in Matlab?

Description. y = filtfilt( b , a , x ) performs zero-phase digital filtering by processing the input data x in both the forward and reverse directions. After filtering the data in the forward direction, the function reverses the filtered sequence and runs it back through the filter.

What does signal filtfilt do?

filtfilt. Apply a digital filter forward and backward to a signal. This function applies a linear digital filter twice, once forward and once backwards.

What is filtfilt Python?

filtfilt, a linear filter that achieves zero phase delay by applying an IIR filter to a signal twice, once forwards and once backwards.