# Suggestion Bold-face for vectors in tex

1. Jan 8, 2012

### Simon Bridge

I don't know how much control admins have over how the tex parser here behaves.

Vectors can be typeset in LaTeX with the command \vec, which decorates the argument with a little arrow.
This was cute at first, but it doesn’t look very good, eg. inline $\vec{r}$, but especially in fractions. $$\frac{2\pi}{\vec{r}}$$Don't get me wrong, it's not horrible ...
Don't mess with that standard.
Alternates to that can be defined, optionally.

$\mbox{my } 3c\!\!\!\!/$

7. Jan 8, 2012

### Simon Bridge

Hmmm ... interesting, I have not the 2010 editions of these books.

Tipler 5th Ed (your example) also uses bold-face-italics with the arrow for vectors.

Perhaps a trend in text-book publishing?
How long have they been doing this for? It's been bf vectors in Tipler, for eg, for something like decades! Oh well.... if popular textbooks are using bf+arrows, then perhaps consistency dictates we do the same?

APS updated their submission standard 2 years ago, and the template was updated in march 2010 ... still uses bold-face: no mention of the arrow form. May be interesting to compare the other journals people use here....

Knuth: I'll concede that the TeX/LaTeX defaults are a de-facto standard. I'll even concede that we don't want to rashly fiddle with the defaults (though some journals - APA for eg - radically alter them). Though I have a few observations which may be argued to weaken the supremacy of Knuth in the case of these forums:

1. Knuth was not a physicist
2. His math-typography reference works were divided on notation styles
3. He emphasized typographical rather than notation styles in the specs
4. He encourages changing the styles and altering his plan
5. He also advocates Computer Modern as the TeX font - do we use that?

I'm very sure the arrow form for \vec was not always there but am having trouble finding a concrete reference. I remember being surprised when it stopped giving me bf.

Leaves me with AMS and ISO standards to base my argument on - if physics standards are important here of course.

Interestingly the AMS reference cards list the vector under accents as over-arrow (math only) despite their actual journals asking for boldface.

Wikipedia uses boldface-upright... but also arrow-over in some diagrams.

Few contributors here are in the position that they will be submitting to journals any time soon, so using major journal standards would be overkill (though nice) ... the textbook argument was strongest but weakened above by the publishers just not playing ball the splitters!

It'll be interesting to see which way the publishers move. Is the bf+arrow thing a fad, here for the long-term, signalling a move to just arrows, or will it fade out.
Having used both now, I can live with either.

For now I'm prepared to rest my case.

8. Jan 8, 2012

### AlephZero

This is a bit of a non-debate using "proper" TeX or LaTeX because you can define a macro for whatever style you or your editor/publisher prefers.

The real problem is that PF Latex doesn't let you define global macros.

I haven't seen any arrows in engineering math for decades, but we all know that "real mathematicians" love inventing new notations even more than they love inventing new math

9. Jan 8, 2012

### Simon Bridge

So you'd have to hack the style sheet or whatever the thingy is using to decide the style to use ... bummer!

10. Jan 9, 2012

### dextercioby

Regarding [itex ], indeed $\frac{\vec{r}}{r^3}$ looks nasty and quite unreadable. Just use \displaystyle before the \frac $\displaystyle{\frac{\vec{r}}{r^3}}$.

11. Jan 9, 2012

### Simon Bridge


I can argue either way - the first one, the vector sits better in the line ... looks like part of the text like a word should. However the second stands out more - making an unmistakable distinction that here is a vector.

Perhaps with high quality printing and computer typesetting now commonplace, bf for vecs is no longer needed the way it used to be? To me, the arrow version looks better inline and the bold-face better for display-math... particularly in presentations.