I think it would be safer to pass a formatter function to `array2string` and dealing with a single value at a time rather than parsing the whole enchilada below.  i.e.:

```
formatter={'float_kind': astropy.units.format.latex.Latex.format_exponential_notation}
```

(assuming `format_exponential_notation` is made public and into a classmethod as I described in a top-level comment.)