string to vector of strings
[s]=str2vec(name,arg1, ,argn)
name = a string
argi = a string indicating a separator
s = a (n x 1) vector of names
str2vec('a=b,c,d',',') // returns //!b ! //!c ! //!d ! grocer_coef=str2vec(grocer_coef) // Example taken from nls: str2vec is used to transform into a vector the list of coefficient names given by the user.