Hello,

I'm having the same issue, but unfortunately the previously-mentioned fix doesn't work for me.  I have MATLAB version R2017b, and from the moment I add gPPI to my path any use of a script or attempt to write a loop in the workspace yields continuous instances of "Operands to the || and && operators must be convertible to logical scalar values."  I attempted the basic example given earlier in this thread and I cannot run it.  Any use of dlmwrite finishes with an error and the same message, with no further explanation.  Even my attempts to diagnose the issue by including disp() commands in dlmwrite to view what is being fed into the command yield an error message.  I've looked into if pathdef.m, disp.m, contains.m, edit.m, and a few other files are shadowed, and a "which" call yields only a single instance for any/all of these, while "which -all" commands indicate that there are multiple same-named commands in different places associated with different methods.  I'm going to keep trying to figure this out, but I could really use some help

Best,
Akos Szekely