A script kept information on potential subjects for an experiment in a vector of structures known as "subjects".  The following show an example of what the contents may be:
>> subjects
subjects =
1x3 struct array with fields:
    name
    sub_id
    height
    weight
>> subjects(1)
ans =
      name: 'Joey'
    sub_id: 111
    height: 6.7000
    weight: 222.2000

For this only experiment, the particluar subjects who are eligible are those whose height or weight is lower than the average height or weight of all subjects.  The script will print the names of those who are eligible.  Make a vector with sample data in a script, and then write the code to accomplish this. Don't suppose that the length of the vector is called as the code should be general.