# Matrices in the Gummi editor?

1. Mar 25, 2015

### Stephen Tashi

What are some examples of writing matrices in the Gummi latex editor? Something about the syntax used on the forum doesn't work for me when used in Gummi.

2. Mar 25, 2015

### Staff: Mentor

Can you show what you tried that doesn't work?

3. Mar 25, 2015

### Stephen Tashi

This example doesn't work when the underlying LaTex is pasted into the Gummi editor:

\begin{pmatrix} 1 & 0 \\ -1 & 1 \end{pmatrix}

4. Mar 26, 2015

### Staff: Mentor

pmatrix is an extension from amslatex. In the preamble of your tex file, add

\usepackage{amsmath}

and it will work. There are many useful extensions in amsmath and I use it in almost all my documents. See the instruction manual.

5. Mar 27, 2015

### Stephen Tashi

Thank you DrClaude.
\usepackage{amsmath} in the preamble makes things behave as expected.