How do I attach a subscript with inline behaviour in display math?

Questions
1

Original

image
image944×182 26.2 KB

My attempt
image

  $
    f arrow.b_(i_(1),...i_(k)) = (m - k)!^(-1) sum_(s in SS_(m-k))^()f(tilde(u) tilde(s) t)
  $

I think “!” with the subscript looks different too than on Latex.

2

hey @rudy,

You can use Attach Functions – Typst Documentation to get the desired effect. By encasing the down arrow with a scripts, this redefines _ or ^ to be placed like super- and subscript (limits has it top and bottom). Also encasing the subscript part in double casing renders the inner braces!

$ f scripts(arrow.b)_((i_(1),...i_(k))) = (m - k)!^(-1) sum_(s in SS_(m-k))^()f(acute(u) grave(s) t) $

image
image836×184 11.8 KB

And the ! looks the same to me :)

And Accent functions can be found in the docs at Accent Function – Typst Documentation!

And I forgot the (u), so don’t forget that one :)

3

I think they mean that the big space between ! and the sum is different?

4

ah oops. Not aware of any parameter to fix this, but a workaround is to use #h(-0.3em) between the sum and !

5

You could use something like the smash function I defined in Smashoperator Analogue - #4 by Eric, though that will remove the extra spacing on both sides of the sum symbol.

3 Likes
6

That’s a much better solution!

8

Hi sorry I do not know why my post got deleted that was an accident.
Thanks for the reply everyone and welcome this is awesome.
What I actually meant about my comment about the ! symbol (though what I wrote then wasn’t even a full sentence, apologies) is that the superscript’s (in this -1) position on it differs from Latex in Typst.

Latex

image

Typst

image

I personally do not mind the difference, both look good, and this may be a New Computer Modern thing, I just want to help find a bug if there is one.

10

I was using the smash operator to try to reduce the distance between the f and the arrow. It seemed to make the symbols smaller however.
Here is the code snippet.

// From: https://forum.typst.app/t/smashoperator-analogue/1763/4?u=rudy
#let smash(body, side: center) = math.display(
  box(
    width: 0pt,
    align(
      side.inv(),
      box(width: float.inf * 1pt, $ script(body) $),
    ),
  ),
)
$
    f scripts(arrow.b)_((i_(1),...i_(k)))
    \
    smash(f scripts(arrow.b)_((i_(1),...i_(k))))
$

And here is the output
image

11

I ended up doing this at the end and I think the output looks great!

  • Use scripts(arrow.b) to place subscript under the arrow
  • Use #h(-.01em) to move the arrow slightly over to the left.
  
  $
    "Way Before"&: f  arrow.b_(i_(1),...i_(k)) = (m - k)!^(-1) sum_(s in SS_(m-k))^()f(tilde(u) tilde(s) t) \
    "Before"&: f  scripts(arrow.b)_(i_(1),...i_(k)) = (m - k)!^(-1) sum_(s in SS_(m-k))^()f(tilde(u) tilde(s) t) \
    "After"&: f #h(-.01em) scripts(arrow.b)_(i_(1),...i_(k)) = (m - k)!^(-1) sum_(s in SS_(m-k))^()f(tilde(u) tilde(s) t)

  $

image
image1236×378 58.8 KB

12

Yes that is not what that function is for. As mentioned in the post I linked, it is meant for getting rid of additional spacing caused by wide sub- or superscripts.

1 Like