# Plot tau(f)¶

Fig. 19 shows a typical view of the $$\pmb{\tau(f)}$$ tab for plotting the group delay, here, an elliptical filter (IIR) is shown.

Fig. 19 Screenshot of the $$\tau(f)$$ tab

There are no user servicable parts on this tab.

The algorithm for calculating the group delay is explained in detail in
pyfda.libs.pyfda_sig_lib.group_delay().

Library with various signal processing related functions