I am currently building a code, which is modified from another freeshare code available online. However, I am unclear how the "extract" function in Matlab works. I have looked through the help menu and searched using Google as well. However, I haven't been able to get much help.
Currently, the extract function used in the code looks like this:
I keep getting the error: ??? Undefined function or method 'extract' for input arguments of type 'double'. whenever I try to run the entire code.
The help menu offers me an explanation on the extract function. However, the extract function in the help menu appears to have an extra parameter added. (i.e. [outmatrix, freq] = extract (h,outtype,z0). It explains that: outtype can be one of these case-insensitive strings 'ABCD_parameters', 'S_parameters', 'Y_parameters', 'Z_parameters', 'H_parameters', 'G_parameters', or 'T_parameters'. z0 is the reference impedance for the S-parameters. The default is 50 ohms.
As such, I'm somewhat convinced the original code (which has been around for some time) is missing a parameter that doesn't allow it to run on newer Matlab versions. But, I am not entirely sure since I'm unsure what z0/reference impedance means in this function.
Would appreciate any help on this, or just any links to website that provides an explanation/example on how to use the "extract" function.