Using makepassive function for passivity correction

I am trying to convert a non-passive touchstone file to a passive one using makepasive function and the code is as follow

S1 = sparameters('Sample_file.s2p');

ispassive(S1)

ans = 0;

S2 = makepassive(S1);

ispassive(S2)

ans = 1;

rfwrite(S2,'NewTouchstone.s2p');

S= sparameters('NewTouchstone.s2p')

ispassive(S2)

ans =0;

I believe the makepassive function converts all the parameters to passive ones and i also get a logical 1 after the conversion.

But after I write it into a touhstone file and do the passivity check again, it fails.

Can somebody help me to understand what might be going wrong.

Answer 1

[shaziah A]

I forgot to attach the touchstone file. I could not attach the snp format and hence have attached the text format, just change the extension to snp while downloading it.