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How to Typeset Equations in LAT
E
X
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4.2 Solution: basic usage of IEEEeqnarray
The IEEEeqnarray-environment is a very powerful command with many options. In
this manual we will only introduce some of the most important functionalities. For
more information we refer to the ocial manual.
5
First of all, in order to be able to
usetheIEEEeqnarray-environment,oneneedstoincludethepackage
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IEEEtrantools.
Includethefollowinglinein theheader ofyourdocument:
\usepackage{IEEEtrantools}
ThestrengthofIEEEeqnarrayisthepossibilityofspecifyingthenumberofcolumns
in theequationarray. Usually, thisspecication will be {rCl}, i.e., threecolumns,the
rst column right-justied, the middle one centered with a little more space around
it (therefore we specify capital C instead of lower-case c) and the third column left-
justied:
\begin{IEEEeqnarray}{rCl}
a & = & b + c
\\
& = & d + e + f + g + h
+ i + j + k \nonumber\\
&& +\> l + m + n + o
\\
& = & p + q + r + s
\end{IEEEeqnarray}
a=b+c
(26)
=d+e+f+g+h+i+j+k
+l+m+n+o
(27)
=p+q+r+s
(28)
However,wecanspecifyanynumberofneededcolumns. Forexample,{c}willgiveonly
onecolumn (which is centered)or {rCll} will add afourth, left-justied column, e.g.,
for additional specications. Moreover, beside l, c, r, L, C, R for math mode entries,
therealsoexistss,t, ufor left, centered,andrighttextmodeentries, respectively. We
can even add additional spacing by . and / and ? and " in increasing order.
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More
details about the usageof IEEEeqnarraywill be given inSection5.
Notethatin contrast toeqnarraythespacesaroundtheequalitysignsarecorrect.
4.3 A remark about consistency
Therearethreemoreissuesthathavenotbeenmentioned sofar, butthatmightcause
inconsistencies whenallthreeenvironments, equation,multline, andIEEEeqnarray,
areused intermixedly:
multline allows for an equation startingon top of a page, while equation and
IEEEeqnarraytrytoputalineoftextrst,beforetheequationstarts. Moreover,
thespacingbeforeandaftertheenvironmentisnotexactlyidenticalforequation,
multline, andIEEEeqnarray.
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TheocialmanualIEEEtran
HOWTO.pdfisdistributedtogetherwiththisshortintroduction.The
partaboutIEEEeqnarraycanbefoundinAppendixF.
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This packageis also distributed together withthis manual,butitisalreadyincluded in anyup-
to-dateLAT
E
Xdistribution. Notethatifa documentuses the IEEEtran-class,thenIEEEtrantoolsis
loadedautomaticallyandmustnotbeincludedseparately.
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Forexamplesofspacing,werefertoSection6.1. Morespacingtypescanbefoundintheexamples
giveninSections5.3and6.8,andintheocialmanual.
c
StefanM.Moser
13March2016,Version4.4