I am implementing a communication system using Matlab, and I had previously done convolutional encoding with puncturing on a binary stream, using `convenc`. However, I checked the documentation for `vitdec` (Viterbi decoding), and this is what I found.

```matlab
decoded = vitdec(code,trellis,tblen,opmode,dectype)
decoded = vitdec(code,trellis,tblen,opmode,'soft',nsdec)
decoded = ... vitdec(code,trellis,tblen,opmode,dectype,puncpat)
decoded = ... vitdec(code,trellis,tblen,opmode,dectype,puncpat,eraspat)
decoded = ... vitdec(...,'cont',...,initmetric,initstates,initinputs) 
[decoded,finalmetric,finalstates,finalinputs] = ... vitdec(...,'cont',...)

```

For the second function definition (with soft decoding), there is no parameter for the puncture pattern vector. How do I go about this?