Other Compositions
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The `csup' function builds a superscripted expression.  For example,
`csup(a, b)' looks the same as `a^b' does in Big language mode.  This
is essentially a horizontal composition of `a' and `b', where `b' is
shifted up so that its bottom line is one above the baseline.

Likewise, the `csub' function builds a subscripted expression.  This
shifts `b' down so that its top line is one below the bottom line of
`a' (note that this is not quite analogous to `csup').  Other
arrangements can be obtained by using `choriz' and `cvert' directly.

The `cflat' function formats its argument in "flat" mode, as obtained
by `d O', if the current language mode is normal or Big.  It has no
effect in other language modes.  For example, `a^(b/c)' is formatted
by Big mode like `csup(a, cflat(b/c))' to improve its readability.

The `cspace' function creates horizontal space.  For example,
`cspace(4)' is effectively the same as `string(" ")'.  A second string
(i.e., vector of characters) argument is repeated instead of the space
character.  For example, `cspace(4, "ab")' looks like `abababab'.  If
the second argument is not a string, it is formatted in the normal way
and then several copies of that are composed together: `cspace(4,
a^2)' yields

      2 2 2 2
     a a a a

If the number argument is zero, this is a zero-width object.

The `cvspace' function creates vertical space, or a vertical stack of
copies of a certain string or formatted object.  The baseline is the
center line of the resulting stack.  A numerical argument of zero will
produce an object which contributes zero height if used in a vertical
composition.

There are also `ctspace' and `cbspace' functions which create vertical
space with the baseline the same as the baseline of the top or bottom
copy, respectively, of the second argument.  Thus `cvspace(2, a/b) +
ctspace(2, a/b) + cbspace(2, a/b)' displays as:

             a
             -
     a       b
     -   a   a
     b + - + -
     a   b   b
     -   a
     b   -
         b