Next: Greek letters, Previous: Delimiters, Up: Math symbols [Contents][Index]
Ellipses are the three dots (usually three) indicating that a pattern continues.
\begin{array}{cccc}
a_{0,0} &a_{0,1} &a_{0,2} &\ldots \\
a_{1,0} &\ddots \\
\vdots
\end{array}
LaTeX provides these.
\cdots
Horizontal ellipsis with the dots raised to the center of the line, as
in ⋯. Used as: \( a_0\cdot a_1\cdots a_{n-1}
\).
\ddots
Diagonal ellipsis, ⋱. See the above array example for a usage.
\ldots
Ellipsis on the baseline, …. Used as: \(
x_0,\ldots x_{n-1} \). Another example is the above array example. A
synonym is \mathellipsis. A synonym from the amsmath
package is \hdots.
You can also use this command outside of mathematical text, as in
The gears, brakes, \ldots{} are all broken. (In a paragraph
mode or LR mode a synonym for \ldots is \dots.)
\vdots
Vertical ellipsis, ⋮. See the above array example for a usage.
The amsmath package has the command \dots to semantically
mark up ellipses. This example produces two different-looking outputs
for the first two uses of the \dots command.
\usepackage{amsmath} % in preamble
...
Suppose that \( p_0, p_1, \dots, p_{n-1} \) lists all of the primes.
Observe that \( p_0\cdot p_1 \dots \cdot p_{n-1} +1 \) is not a
multiple of any \( p_i \).
Conclusion: there are infinitely many primes \( p_0, p_1, \dotsc \).
In the first line LaTeX looks to the comma following \dots to
determine that it should output an ellipsis on the baseline. The second
line has a \cdot following \dots so LaTeX outputs an
ellipsis that is on the math axis, vertically centered. However, the
third usage has no follow-on character so you have to tell LaTeX what
to do. You can use one of the commands: \dotsc if you need the
ellipsis appropriate for a comma following, \dotsb if you need
the ellipses that fits when the dots are followed by a binary operator
or relation symbol, \dotsi for dots with integrals, or
\dotso for others.