Is symprec in units of angstroms?

Seems likely, but I didn’t want to assume:

https://pymatgen.org/pymatgen.symmetry.analyzer.html#pymatgen.symmetry.analyzer.SpacegroupAnalyzer

Many of the symmetry tools in pymatgen build upon spglib, this is where the definition of the symprec and angle_tolerance come from: Variables — Spglig v.1.16.0

Hope this helps!

Matt

@mkhorton, thanks! This does help. Based on the paper, it seems like this is a relative precision that depends on the dimensions of the unit cell:
image

To be sure though, I’m asking for clarification at:

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It is Cartesian. The distance unit is the same as the user’s input of (a, b, c)

So, it seems to be an absolute tolerance in Angstroms for pymatgen, assuming that get_hall_number_from_symmetry isn’t the main function being used in pymatgen to accomplish this.

See clarify documentation of symprec? · Issue #74 · spglib/spglib · GitHub (comment) and thread for more details.

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