vector to timeseries
[tsout]=vec2ts(vector,boun)
* vector = a (1xn) or (nx1) vector
* boun = a (1xn) or (nx1) string vector of bounds
* tsout = the corresponding timeseries
t=vec2ts([1:24 28:32],['1a' ; '24a' ; '28a' ; '32a']) // Creates a ts which is a time trend from 1a to 32a, with three nan values between 25a and 27a.