# Symbols:General/Ellipsis

## Ellipsis

- $\ldots$ or $\cdots$

An **ellipsis** is used to indicate that there are omitted elements in a set or a sequence whose presence need to be inferred by the reader.

For example:

- $1, 2, \ldots, 10$

is to be understood as meaning:

- $1, 2, 3, 4, 5, 6, 7, 8, 9, 10$

There are two forms of the horizontal **ellipsis**, one on the writing line which is to be used for punctuation separated lists:

- $a, b, \ldots, z$

and one centrally placed in the line, to be used in other circumstances, for example, in expressions assembled using arithmetic operations:

- $a + b + \cdots + k$

There also exist vertically and diagonally arranged ellipses, for use in the structure of matrices:

- $\begin{array}{c} a \\ \vdots \\ b \end{array} \qquad \begin{array}{c} a \\ & \ddots \\ & & b \end{array}$

The $\LaTeX$ code for \(1, 2, \ldots, 10\) is `1, 2, \ldots, 10`

.

The $\LaTeX$ code for \(1 + 2 + \cdots + 10\) is `1 + 2 + \cdots + 10`

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The $\LaTeX$ code for \(\vdots\) is `\vdots`

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The $\LaTeX$ code for \(\ddots\) is `\ddots`

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## Linguistic Note

The plural of **ellipsis** is **ellipses**.

This is pronounced **ell- ip-seez**, where the final syllable is long.

Do not confuse with the plural of ellipse, which is spelt the same but is pronounced **ell- ip-siz**.