I often import .snp files using data items (like ads_datacmps:S2P) with porst connected to its terminals, and then make the data from the file available by running an S-Parameter simulation.
When I have more than one file import in my schematics some of the S-Parameters I get as a result of simulation are useless. For instance, if I want to import two s2p-files I will use two S2P components from ADS and then connect Port impeadances Term1 and Term2 to the first S2P and Term3&Term4 to the second S2P.
Since I have four Terms in my schematic I will get the total of 16 S-Parameters, eight of which are useless - for instance S31 presents no information to me in this setup.
If I want to plot the data I need to browse through many S-Parameters containing no data. Is there any way of switching off the unnecessary SParameters or maybe an import method allowing avoiding the generating of unnecessary S-parameters ?
S-parameter matrixes are square so to calculate S11, S12, S21 and S22 then you will always get S13, S14, S23 and S24 for a 4 port network. Similar for ports 3 and 4. There is no way to disable those 'unwanted' values.
If the goal is to simply read 2 port s-parameter data from a Touchstone S2P file into a dataset so that it can be used for graphs in the Data Display why are you using simulation? You can simply use the Tools > Data File Tool... from the either the Schematic or Data Display menus to read each S2P file data into a dataset directly. You can then access the dataset to draw any graphs required without the unwanted data being generated.