How to manipulate an array

I have three excel spread sheets. They are 17 columns by 4800 rows. I need to divide the last time point entry for each subject (column 17) by the number of data points (length of that array) for that subject. I am not sure what code is needed. Thank you!

[Hyeokjin Jho]

I think question is bit unclear. So you need to divide each element in column 17 by number 17?

[madhan ravi]

Could you upload a sample?

[Jacob Wood]

Brady,

Are you able to read in the Excel table to a Matlab array? Some functions of interest here might be xlsread() or readtable().

After you have an array you can find the number of data points, or the height of the array, with size(A,1). You can use this value to write the 18th column of data.

Finally, you can write out the data with a function like xlswrite() or writetable().

Best, Jacob