Generally speaking, if you have samples that are not marked with a corresponding time, but you know the starting time (such as 0) and you know the sampling frequency, then you can calculate times as
time_vector = (0:number_of_samples-1) ./ SamplingFrequency;
number_of_samples would typically have been extracted using size() of an array. SamplingFrequency would have to be known ahead of time (or extracted from the information available in the dataset.)
