PauliOrder[exp] orders the Pauli matrices in expr alphabetically.
PauliOrder[exp, orderlist] orders the Pauli matrices in expr according to orderlist.
CSI[k, j, i]
PauliOrder[%]\overline{\sigma }^k.\overline{\sigma }^j.\overline{\sigma }^i
2 \overline{\sigma }^i \bar{\delta }^{jk}-2 \overline{\sigma }^j \bar{\delta }^{ik}+2 \overline{\sigma }^k \bar{\delta }^{ij}-\overline{\sigma }^i.\overline{\sigma }^j.\overline{\sigma }^k
CSID[i, j, k]
PauliOrder[%]\sigma ^i.\sigma ^j.\sigma ^k
\sigma ^i.\sigma ^j.\sigma ^k
PauliOrder[%%, {j, i, k}]2 \sigma ^k \delta ^{ij}-\sigma ^j.\sigma ^i.\sigma ^k