Hfrhyu

I am trying to write some matrices with latex in Keynote and I cant make them the same height. There are some answers to this problem but can't make them work in Keynote.

The equation looks like this:

 beginpmatrix
 X'hat R^-1X & X'hat R^-1Z_1 & X'hat R^-1Z_2 & X'hat R^-1Z_3 \
 Z'_1hat R^-1X & Z'_1hat R^-1Z_1 + G^-1_1& Z'_1hat R^-1Z_2 & Z'_1hat R^-1Z_3 \
 Z'_2hat R^-1X & Z'_2hat R^-1Z_1 & Z'_2hat R^-1Z_2 + G^-1_2& Z'_2hat R^-1Z_3 \
 Z'_3hat R^-1X & Z'_3hat R^-1Z_1 & Z'_3hat R^-1Z_2 & Z'_3hat R^-1Z_3 + G^-1_3
 endpmatrix 
 beginpmatrix
 alpha \ 
 gamma \ 
 delta \ 
 epsilon 
 endpmatrix 
 = 
 beginpmatrix
 X'hat R^-1y \
 Z'_1hat R^-1y \
 Z'_2hat R^-1y \
 Z'_3hat R^-1y
 endpmatrix

And I get:

As Keynote.app uses a limited set of LaTeX commands (see this page), we cannot have a perfect result. In particular, there's not a vphantom command available. But with phantomhatI_. before alpha etc., we obtain a not so bad result.

beginpmatrix
 X'hat R^-1X & X'hat R^-1Z_1 & X'hat R^-1Z_2 & X'hat R^-1Z_3 \
 Z'_1hat R^-1X & Z'_1hat R^-1Z_1 + G^-1_1& Z'_1hat R^-1Z_2 & Z'_1hat R^-1Z_3 \
 Z'_2hat R^-1X & Z'_2hat R^-1Z_1 & Z'_2hat R^-1Z_2 + G^-1_2& Z'_2hat R^-1Z_3 \
 Z'_3hat R^-1X & Z'_3hat R^-1Z_1 & Z'_3hat R^-1Z_2 & Z'_3hat R^-1Z_3 + G^-1_3
 endpmatrix 
 beginpmatrix
 phantomhatI_.alpha \ 
 phantomhatI_.gamma \ 
 phantomhatI_.delta \ 
 phantomhatI_.epsilon 
 endpmatrix 
 = 
 beginpmatrix
 X'hat R^-1y \
 Z'_1hat R^-1y \
 Z'_2hat R^-1y \
 Z'_3hat R^-1y
 endpmatrix

For better result, and true LaTeX output, I suggest the use of the app LaTeXit, which is installed by a default MacTeX distribution. With this app, you can export transparent vectoriel images of equations to Keynote.app, and modify it later if needed.

(It's been pointed out that this solution cannot work with Keynote, since that app knows only a rather limited subset of TeX and LaTeX commands. In particular, vphantom isn't understood by Keynote. I've decided not to delete this answer, though, as it might come in handy some day for some readers not tied to Keynote.)

You could insert suitably defined typographic struts in each element of the "short" vector.

documentclassarticle
usepackageamsmath % for 'pmatrix' environment
newcommandmystrutvphantomZ'_3hR 
newcommandhRhatR^-1 % handy shortcut macro
begindocument
[
beginpmatrix
 X'hR X & X'hR Z_1 & X'hR & X'hR Z_3 \
 Z'_1hR X & Z'_1hR Z_1 + G^-1_1& Z'_1hR Z_2 & Z'_1hR Z_3 \
 Z'_2hR X & Z'_2hR Z_1 & Z'_2hR Z_2 + G^-1_2& Z'_2hR Z_3 \
 Z'_3hR X & Z'_3hR Z_1 & Z'_3hR Z_2 & Z'_3hR Z_3 + G^-1_3
endpmatrix 
beginpmatrix
 alphamystrut \ 
 gammamystrut \ 
 deltamystrut \ 
 epsilonmystrut 
endpmatrix 
= 
beginpmatrix
 X'hR y \
 Z'_1hR y \
 Z'_2hR y \
 Z'_3hR y
endpmatrix
]
enddocument