I’ve manually defined a new variable like so:
let y_metres = {1.74779531E+05, 1.74779531E+05, 1.76507196E+05, 907E+05,
[. . . ]
1.74779531E+05, 1.74779531E+05}
This new variable (y_metres) is automatically put on the I axis. I was wondering how I might specify it to be on the J axis.