flag = issos(sysobj)
determines whether the filter System object™ is in second-order sections (SOS) form, returning a logical
1 if true and a logical 0 if false.
flag — Flag to determine if filter is in SOS form 1 | 0
Flag to determine whether the filter is in second-order sections (SOS) form,
returned as a logical scalar. If the filter is in SOS form, issos
returns a logical 1, else it returns a logical
0.