Array variable in G-code

Hello folks! I am wondering about is there any way to define an array variable in G-code? The main reason makes me wanna know this is about aligning columns in my log file. I am doing some repeated measurement operations in forward and reverse way. During this process, if i log the data one after another, rows are being increased in my log file, and i need to arrange that file to align forward and reverse measurements in excel by myself. I think keeping the data in the array can be solution. 

Thank you for your time,
Berkay

Yes, sort-of.

This is a valid syntax:

This would store the value of 25.4 in the parameter #103

Thank you for your answer Andy.
Is there any discord channel or something like that to discuss these kind of topics? It would be great if i can join that channel.