[texhax] align, align*, nonumber and ??

[Victor Ivrii]

On Fri, Oct 3, 2008 at 3:48 AM, Edsko de Vries <edsko at edsko.net> wrote:
> On Thu, Oct 02, 2008 at 10:28:19PM +0200, Christian H. Aastrup wrote:
>> Hi there!
>>
>> When I write
>>
>> \begin{align}
>> a&=b\nonumber
>> \\
>> &=c \nonumber
>> \\
>> &=d
>> \end{align}
>>
>> I only get at number in the last line. But I want to do this in align and
>> need a command that makes a number rather than suppress it
>>
>> \begin{align*}
>> a&=b
>> \\
>> &=c
>> \\
>> &=d \yesnumber
>> \end{align*}
>>
>> Does such a \yesnumber command exist?

Not sure why one should not use {align} with \notag for all others


>
> I don't know of a predefined one, but in my thesis I use:
>
> % sometimes it is useful to tag some equations in an align* block but not
> % others; \newtag can be used for this purpose
> \newcommand{\newtag}{\tag{\theequation}\addtocounter{equation}{1}}


Better
\stepcounter{equation} or
\refstepcounter{equation} (if with hyperref)
instead of
\addtocounter{equation}{1}
>




-- 
========================
Victor Ivrii, Professor, Department of Mathematics, University of Toronto
http://www.math.toronto.edu/ivrii