Is the matrix centrosymmetric... and so is the code?
JavaScript (ES6), size 12 11 9

All versions return false for centrosymmetric or true for non-centrosymmetric.



1-dimensional array + length, size 9 (89 bytes)

Takes input in currying syntax (length)(array), where array is 1-dimensional.



w=&gt;a=&gt; //
a.some //
(v=&gt;v- //
a[--w])//
/////////
//)]w--[a
// -v&gt;=v(
// emos.a
// &gt;=a&gt;=w


Try it online!



Matrix + width, size 11 (131 bytes)

Takes input in currying syntax (width)(matrix).



/**/w=&gt;a=&gt;a
.some(r=&gt;r.
some(v=&gt;v-a
[y][w-++x],
x=!y--),y=w
);'*/'/*';)
w=y,)--y!=x
,]x++-w[]y[
a-v&gt;=v(emos
.r&gt;=r(emos.
a&gt;=a&gt;=w/**/


Try it online!

Payload

w =&gt; a =&gt; a.some(r =&gt; r.some(v =&gt; v - a[y][w - ++x], x = !y--), y = w)


Container

/**/CODE;'*/'/*';EDOC/**/




Matrix only, size 12 (155 bytes)

This is my original solution, which computes the width of the matrix by itself.

/**/a=&gt;a[w=a
.length-1,s=
'some']((r,y
)=&gt;r[s]((v,x
)=&gt;v-a[w-y][
w-x]))////*/
/*////))]x-w
[]y-w[a-v&gt;=)
x,v((]s[r&gt;=)
y,r((]'emos'
=s,1-htgnel.
a=w[a&gt;=a/**/


Try it online!

How?

We need a few critical tokens that cannot be split:


some
length
)=&gt;


Line-feeds may be inserted almost anywhere else.

The unrolled payload code reads as:

a =&gt; a[w = a.length - 1, s = 'some']((r, y) =&gt; r[s]((v, x) =&gt; v - a[w - y][w - x]))


and is wrapped inside the following structure:

/**/CODE////*/


which, once reversed, becomes a valid block comment:

/*////EDOC/**/