# Equivalent of LaTeX “eqnarray” in Microsoft Word 2007 equation editor?

In LaTeX one can use the eqnarray environment to display a set of equations aligned horizontally on their equality signs or other element, e.g.:

\begin{eqnarray*}
x &=& 5! \\
&=& 5 \cdot 4 \cdot 3 \cdot 2 \cdot 1
\end{eqnarray*}


This will render as follows (notice the alignment of the equality signs):

Is there a good way to achieve the same effect in Microsoft Word 2007's built in equation editor?

Not exactly, but this site has some good introductory material. The equation editor is a bit more visual than latex:

Enter the following equations and align them at the = sign by choosing Format/Align At = after typing them. Also try using the alignment symbol - - to align equations.

• I found a bit more up-to-date article on MSDN. The question and answer relevant are the first and second comment. blogs.msdn.com/microsoft_office_word/archive/2006/10/04/… – akid Apr 10 '10 at 8:24
• The msdn article is newer, but covers much less material, which is why I linked to the Univ. of waterloo site. – DaveParillo Apr 10 '10 at 20:51
• Thanks! akid's comment in particular pointed right to the solution, which was to select all the relevant equations, right-click on them, and then click "Align on =". Unfortunately it seems Word 2007 is still unreliable when it comes to editing equations; I aligned my equations as described then saved and closed the document, and when I reopened it many of the equations were randomly misaligned or typeset in bold face. So it looks like I'm using LaTeX for this project after all, but thanks again for your help. – mshroyer Apr 10 '10 at 21:30
• If you're having difficulties with latex & are looking for something about as powerful but a bit easier, you might try Lyx: lyx.org – DaveParillo Apr 10 '10 at 23:36

What you're after is an "equation array", which is invoked in MS Equation Editor with \eqarray.

It's borrowed from LaTex.

Type Alt-= then:

\eqarray(x+1&=2@1+2+3+y&=z@3/x&=x) <space>


You'll get:

Nice!

As you can tell, an new line (equation) is started with @. Within an equation, the &'s alternate between telling it what to align at and where to put the spaces needed to perform that alignment. In the above example, there's only one & per line, so each is only telling Equation Editor which character to align at.

So this expression: \eqarray(10&x+&3&y=2@3&x+&13&y=4)

In the first equation we're saying "putting spaces before (implied) align at x. And put spaces before 3 to align align at y".

We'll get this:

Apparently this ingenious (or ridiculous?) method comes from the Unicode standard.

As far as I can tell, you can't edit the alignment after you hit space and cause the rendering. But, you can copy the equation, then paste it as text within the document and get the un-rendered code back. Edit, go outside the parentheses and hit space, and your edited version is now rendered.

Undo also works to un-render it.

Note that you've always been able to select multiple equations, right-click, and "select at =". This is less flexible, and in my experience, doesn't always work right.

[1] Reference