# scipy.signal.tf2sos¶

scipy.signal.tf2sos(b, a, pairing='nearest')[source]

Return second-order sections from transfer function representation

Parameters
barray_like

Numerator polynomial coefficients.

aarray_like

Denominator polynomial coefficients.

pairing{‘nearest’, ‘keep_odd’}, optional

The method to use to combine pairs of poles and zeros into sections. See zpk2sos.

Returns
sosndarray

Array of second-order filter coefficients, with shape (n_sections, 6). See sosfilt for the SOS filter format specification.

Notes

It is generally discouraged to convert from TF to SOS format, since doing so usually will not improve numerical precision errors. Instead, consider designing filters in ZPK format and converting directly to SOS. TF is converted to SOS by first converting to ZPK format, then converting ZPK to SOS.

New in version 0.16.0.

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