[NTG-context] Re: Fractions

Hello fraction fascinated friends,

On Dec 10, 2023, at 5:24 AM, Henning Hraban Ramm wrote:

Am 09.12.23 um 23:30 schrieb Mikael Sundqvist:

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Hi, On Sat, Dec 9, 2023 at 4:39 PM Wolfgang Schuster wrote:

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Fabrice Couvreur schrieb am 09.12.2023 um 17:19:

Very clear ! In typography for Mathematics books, what choice should we make for the best possible result ?

A question better answered by Mikael or Aditya!

Thank you for your trust, Wolfgang. I am not sure I have something valuable to say in addition to Adityas suggestion \frac{1/3} in inline math. In any case, I attach a passage, with suggestions inspired by Lansburgh's book (iin Swedish). Not sure the file size makes it through to the list, though.

Thank you!

I usually only need simple inline fractions like 1/n, 1/2 or 3/8 in text. With these and \frac, the spacing below the numerator (depth) is too big, while the denominator sticks too tightly to the fraction bar. (Of course I use regular numbers for fractions, not mediaeval.)

Usually I’d prefer “vulgar fractions”, but \vulgarfraction looks “horrible” in comparison to the few usual fractions contained in fonts (like ½ & ¾).

I tried to use the OpenType fraction features to no avail.

So I’m still looking for “the best” solution for simple fractions inline.

Hraban

I also use fractions frequently, so I’ve tried a few things. Some fonts have superior and inferior numbers that can be used to make small slash fractions. I’ve done this, but my method is not pretty. Hraban suggested using font features for this, but I haven’t learned how to do that. Any advice is welcome. Example code below uses the Libertinus font, which has these superior and inferior numbers, to produce sample paragraph demonstrating a few options for fractions in text. Gavin \usetypescriptfile[libertinus] \setupbodyfont [libertinus,11pt]% \setupinterlinespace[line=3.1ex] \define\fracone{\getnamedglyphdirect{libertinus}{onesuperior}} % 1 \define\fracthree{\getnamedglyphdirect{libertinus}{threesuperior}} % 3 \define\fracnine{\getnamedglyphdirect{libertinus}{ninesuperior}} % 9 \define\thirteenths{\textfraction\getnamedglyphdirect{libertinus}{oneinferior}\getnamedglyphdirect{libertinus}{threeinferior}} % /13 \define\onethirteenth{\text{\fracone\thirteenths}} % 1/13 \define\threethirteenths{\text{\fracthree\thirteenths}} % 3/13 \define\ninethirteenths{\text{\fracnine\thirteenths}} % 9/13 \starttext Some small fractions are already available in many fonts, like \onehalf\ and \onethird. Others can be built using superior and inferior numbers in some fonts. This includes the fractions required to find the normal and shearing stresses on an oblique plane defined by $l=\sqrt{\threethirteenths}$, $m=\sqrt{\onethirteenth}$, and $n=\sqrt{\ninethirteenths}$. Of course, you could just find the normal and shearing stresses on an oblique plane defined by $l=\sqrt{3/13}$, $m=\sqrt{1/13}$, and $n=\sqrt{9/13}$. Vulgar fractions are between these extremes. Find the normal and shearing stresses on an oblique plane defined by $l=\sqrt{\vfrac{3}{13}}$, $m=\sqrt{\vfrac{1}{13}}$, and $n=\sqrt{\vfrac{9}{13}}$. I included more text than strictly necessary in this example to demonstrate the effect on line spacing. \stoptext