hats also represent estimates

[davharris]

Nice project. In my line of work, the "hat" over variables typically means that the variable is an estimate of some unknown quantity. An example is here: http://mathworld.wolfram.com/MaximumLikelihood.html

The maximum likelihood estimate for a parameter mu is denoted mu-hat.

[mattdesl]

Thanks, I'm going to add a note at the top about ambiguity.

Right now I'm going to mostly focus on language and notations as they appear in graphics/game/interactive applications. I'll definitely accept PRs for other disciplines and uses though. 😄

[davharris]

Great, thanks.

[allo-]

Hat has many many uses.
For example: "Let hat a be the normed vector a /||a||" or "let hat a be c*a for an arbitrary c" or "let hat a be a in another basis, then ...". It's more like tick (') or tilda ~, it's put above a symbol, when you want to say "its kind of the same thing with one special property" or "its derived from ...".

It would be best to describe some cases AND cite some example papers, so the reader can see "okay, if the author describes the notation like this, i could program it like that" and understands that there may be more uses.

[mattdesl]

It would be best to describe some cases AND cite some example papers, so the reader can see "okay, if the author describes the notation like this, i could program it like that" and understands that there may be more uses.

Yeah, definitely. 👍

[allo-]

I guess the problem is wanting to define â here. Define "unit vector" and "maximum likelihood estimate" instead.

And then the user reads "Let \hat a be a unit vector ..." and looks up unit vector and assumes â is one for the rest of the paper (just like the mathmatician does when reading the sentence). Or in code: â = "unit_vector" ;)