Hi, I am writing a mex file where one of inputs is structure array. The structure array is a 1xN array in which each element is a structure and each structure has M fields. In mex file, i want to know number of elements (N) of this structure array. Which function should i use ? If i would like to access a field of each element , what should i do ? Can you give me some suggestions? An detailed explanation will be appreciated!!! I am looking forward to your reply! Thanks in advance!