On Mon, 11 May 2009, Xan wrote:

Hi,

I read the document "Using \startalign and friends" of Aditya (that it's good) and I can't find anything under ams aligned. Is this an equivalent in ConText?

Strictly speaking, none. You can fake aligned and gathered with matrices.

For example, what is the equivalent of:

\begin{equation*} \left.\begin{aligned} & 2^2 | n_0\\ & 4^2 | n_0 + 2 \Rightarrow (2^2)^2 | n_0 +2 \Rightarrow 2^2 | n_0 +2 \text{ ya que } 2^2 | (2^2)^2 \end{aligned}\right\} \Rightarrow 2^2 | (n_0 + 2 - n_0) \Rightarrow 2^2 | 2 \end{equation*}

in ConTeXt?

I tried something like:

\startformula \startmathalignment \NC \startaligned \NC \lambda_{0, \lvert k - s \rvert} (n) \NC < f(n) \NR \NC \text{ per a $n$ suficientment gran } \NC \NR \stopaligned \NC \iff \startaligned \NC \lambda_{s, k} (n) \NC < f(n) \NR \NC \text{ per a $n$ suficientment gran } \NC \NR \stopaligned \NR[+] \NC \lambda_{s, k} (n) < f(n) \text{ per a $n$ suficientment gran } \NC \iff \lambda_{0, \lvert k - s \rvert} (n) < f(n) + C \text{ per a $n$ suficientment gran } \NR[+] \stopmathalignment \stopformula

but " Undefined control sequence" appears to me.

Of course. The command \startaligned is not defined. Here is one way to do this. \definemathmatrix[rightbrace] [align=left, left={\left.}, right={\right\}}, style=\displaystyle] \starttext \startformula \startrightbrace \NC 2^2 | n_0 \NR \NC 4^2 | n_0 + 2 \Rightarrow (2^2)^2 | n_0 +2 \Rightarrow 2^2 | n_0 +2 \text{ ya que } 2^2 | (2^2)^2 \NR \stoprightbrace \Rightarrow 2^2 | 2 \stopformula \stoptext I would also use \implies instead of \Rightarrow (slightly different spacing). Aditya