Let tofu-optics users do this:

import tofu.optics.syntax.tupleN._

val lense = Tuple3._2[Int, String, Long]   // : Contains[(Int, String, Long), String]

tupleN object should contain all possible implicit extensions to Tuple{N} companion objects. Implementations should be macro generated.

Describe the bug
If eps_r is shape (N,) then the fields solved are shape (N,1)

Either:

• disallow 1-D eps_r arrays
  Or:
• keep track of eps_r shape and reshape the fields to match.

Presently, interferometric data can only be written out to ascii files, and read from dat or datx files. The code that handles this in prysm.io should be refactored to allow reading and writing of all formats.