Xjyuk

The intersection of horizontal clines and vertical lines in tables look weird. Here is a MWE:

documentclass[11pt,oneside]article
%usepackagearray

begindocument

begintable
centering
begintabularc
cline2-3
a&b&c&d\
cline2-3
endtabular 
endtable

enddocument

Here is the output:

As you can see, there are small gaps at the intersections of the horizontal and the vertical lines at the two corners at the bottom. Interestingly, the two corners at the top are fine.

Now if the array package is loaded (simply uncomment in the code above), then I get:

The weird gap is gone at the lower right corner but it still persists at the lower left corner.

I did a considerable amount of research into this (see, e.g., this post) but did not find any definitive solution. Any suggestions would be greatly appreciated.

(I am aware of the existence of hhline but I read in another post that it might be prone to similar intersection issues, so I’d prefer a solution without it.)

You get precise control with hhline:

documentclassarticle
usepackagehhline

begindocument

begintabularc
hhline~
a&b&c&d\
hhline~
endtabular

enddocument

• 
  ~ means no rule for the cell,


• 
  | means an intersection with a vertical rule,


• 
  - means a rule for the cell.

Don't know why it happens, but here's a fix...diminish the \ by arrayrulewidth (EDITED to reflect arrayrulewidth rather than fboxrule, hat tip: David Carlisle).

documentclass[11pt,oneside]article
%usepackagearray

begindocument

begintable
centering
begintabularc
cline2-3
a&b&c&d\[-arrayrulewidth]
cline2-3
endtabular 
endtable

enddocument

If one is concerned that this approach shrinks the height of the cell by -arrayrulewidth, then just compensate by adding an extra arrayrulewidth to the depth of the line before the shrunken \. Compare the original box on the left with the revised on the right.

documentclass[11pt,oneside]article
%usepackagearray
newcommandmystrutrule[dimexpr-dpstrutbox-arrayrulewidth]0pt%
 dimexprbaselineskip+arrayrulewidth
begindocument

begintable
centering
begintabularc
cline2-3
a&b&c&d\
cline2-3
endtabular%
%
begintabularc
cline2-3
a&b&c&dmystrut\[-arrayrulewidth]
cline2-3
endtabular 
endtable

enddocument