## Hypertext Help with LaTeX

### Variable size symbols

The size of some mathematical symbols, notably summation
signs, product signs, and integral signs, depends on the
environment in which they appear (i.e., `displaymath` as
opposed to `math` environments; see
Math Formulas and
Math Fonts and Styles).

These include

`\sum`a summation sign (capital sigma)`\prod`a product (capital pi)`\coprod`a coproduct (inverted capital pi)`\int`an integral sign`\oint`a surface (circular) integral sign`\bigcup`big "U"`\bigcap`big inverted "U"`\bigvee`big "V"`\bigwedge`big inverted "V"`\bigodot`big "O" with dot at center`\bigotimes`big "O" with cross inside`\bigoplus`big "O" with a + inside`\biguplus`big "U" with a + inside

The `\sqrt` command also
produces a variable size symbol appropriate for the size of the
radicand argument.

The "limits" associated with these symbols are entered as
subscripts for entries appearing
below the symbol and as superscripts
for entries appearing above the symbol. For example the sum from
n=0 to infinity of x_{n} would be entered as ,/p>

\sum_{n=0}^{\infty} x_{n}

The actual placement of the limits depends on whether this is
in `displaymath` mode in which case they are placed
below/above or in `math` mode in running text in which
case they are placed as regular subscripts and superscripts.

Note that it is possible to treat several of these symbols (a
common example would be a double sum) as a single symbol for
placing limits above and/or below by using the
`\mathop` command.

"Hats" and "tildes" over symbols which stretch (as best they
can) to the correct size for their arguments are produced by
`\widehat` and
`\widetilde`.

Related topics:

- Delimiters can be made variable sized
- Math fonts and styles

- Math Formulas
- Math Symbols
- Math Miscellany
- Arrows
- Binary and relational operators
- Math function symbols
- Miscellaneous symbols

Back to the LaTeX Table of Contents

Revised 28 Nov 1995.