Other Supported File Formats

The data structure for other file types are provided in order to understand and correctly use or post-process these files externally.

.cgm files

This file contains the number of iterations and the resulting residue from the iterative solving process of the matrix equation.

.snp files

The Touchstone S-parameter file name contains the number of ports in the model. The extension is, for example, .s1p for a 1-port, .s2p for a 2-port. The file contains a header (following the “#” character) that specifies the frequency unit, the parameter type, the data format and the normalising impedance for all the ports. This is followed by the data lines (which may be repeated for multiple frequencies):

1-port: frequency | S 11 | ∠ S 11  
2-port: frequency | S 11 | ∠ S 11 | S 21 | ∠ S 21 | S 12 | ∠ S 12 | S 22 | ∠ S 22
3-port: frequency | S 11 | ∠ S 11 | S 12 | ∠ S 12 | S 13 | ∠ S 13  
  | S 21 | ∠ S 21 | S 22 | ∠ S 22 | S 23 | ∠ S 23
| S 31 | ∠ S 31 | S 32 | ∠ S 32 | S 33 | ∠ S 33
4-port: frequency | S 11 | ∠ S 11 | S 12 | ∠ S 12 | S 13 | ∠ S 13 | S 14 | ∠ S 14
  | S 21 | ∠ S 21 | S 22 | ∠ S 22 | S 23 | ∠ S 23 | S 24 | ∠ S 24
| S 31 | ∠ S 31 | S 32 | ∠ S 32 | S 33 | ∠ S 33 | S 34 | ∠ S 34
| S 41 | ∠ S 41 | S 42 | ∠ S 42 | S 43 | ∠ S 43 | S 44 | ∠ S 44
where | S 11 | is the absolute value and ∠ S 11 is the phase (in degrees) of the given parameter.
Note: The 2-port file is formatted on a single line and in a different order than for cases with more ports. This is consistent with the Touchstone file format specification version 1.0.

When exporting results to Touchstone format, the Solver writes out the port labels to commented lines indicated by “!”.

The port labels are written out in chronological order in the following format:
! %Port labels%
! %PortLabel|ModeText[.m][.n][.RotationText]

where the port name is absent or empty, the line will only consist of the “%” symbol.

For example:
! %Port labels%
! %PORT1|TE.1.1.rotation(0)
! %PORT2|TE.1.1.rotation(0)
! %PORT2|TE.1.1.rotation(90)
! %AEPort
! %
! %A1Port

.sph files

This file makes use of the native SWE file format of TICRA as used in their code GRASP.