add instructions on units in the documentation

[jdannberg]

No description provided.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (dbc57f8) 93.55% compared to head (a355f0d) 93.55%.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #582   +/-   ##
=======================================
  Coverage   93.55%   93.55%           
=======================================
  Files          92       92           
  Lines        6346     6346           
=======================================
  Hits         5937     5937           
  Misses        409      409           

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[github-actions]

Benchmark	Main	Feature	Difference (99.9% CI)
Slab interpolation simple none	1.022 ± 0.006 (s=457)	1.022 ± 0.005 (s=426)	-0.1% .. +0.1%
Slab interpolation curved simple none	1.028 ± 0.007 (s=456)	1.028 ± 0.006 (s=422)	-0.1% .. +0.1%
Spherical slab interpolation simple none	1.264 ± 0.007 (s=344)	1.264 ± 0.015 (s=370)	-0.2% .. +0.3%
Slab interpolation simple curved CMS	1.099 ± 0.003 (s=415)	1.100 ± 0.004 (s=406)	-0.0% .. +0.1%
Spherical slab interpolation simple CMS	1.860 ± 0.007 (s=239)	1.858 ± 0.006 (s=248)	-0.2% .. -0.0%
Spherical fault interpolation simple none	1.272 ± 0.004 (s=363)	1.272 ± 0.004 (s=347)	-0.0% .. +0.1%
Cartesian min max surface	2.386 ± 0.024 (s=178)	2.384 ± 0.015 (s=202)	-0.4% .. +0.2%
Spherical min max surface	7.365 ± 0.141 (s=70)	7.349 ± 0.029 (s=55)	-1.0% .. +0.6%