On Sun, Jul 25, 2004 at 10:31:24PM -0700, Brooks Moses wrote:

First, by way of introduction: I've been using LaTeX for about five years now, but am quite new to ConTeXt. I'm a grad student in mechanical engineering, so my primary uses of ConTeXt in the near future are likely to be for my thesis and associated presentations, all of which will likely have lots of complicated equations in them.

In general, it will be very helpful to know how things can be done in plain tex. This should always work in context.

After looking at what documentation is available for this, I think I have a fair handle on the basics of including math in ConTeXt. However, I do have some questions about things beyond the basics that I use rather frequently, and I haven't been able to find useful answers in the documentation or the list archives.

To begin with, I have the following sets of definitions in my standard LaTeX preamble. I know that \newcommand and \renewcommand are LaTeX-specific; what's the appropriate ConTeXt equivalent? Also, do \hat, \vec, and \overline work as I would expect? And is there a direct equivalent to \boldsymbol from the amsmath package? (I need something that will handle both roman and greek letters.)

I have been away from context for some time, but I know that Giuseppe Bilotta has spent much effort on extending its math capabilities. I think he has written some modules providing amsmath features. But he will probably comment on this in more detail and in a more qualified way than I can.

\renewcommand{\vec}[1]{{\boldsymbol{#1}}} \renewcommand{\hatn}{\hat{\vec{n}}} \newcommand{\filter}[1]{\overline{#1}}

You can use the tex primitve \def\vec#1{{\boldsymbol{#1}} or the context way \define[1]\vec{{\boldsymbol{#1}} But afaik there is no checking if a command is already defined? -- Eckhart

Hi Brook, sorry for the horrible delay with which I'm replying to you. I think I have a part of the solution to your problems. Monday, July 26, 2004 Brooks Moses wrote:

Also, many of these equations run over multiple lines using the macros from the amsmath package (the "split" environment in particular, but also the "align" environment), and I haven't been able to find much documentation on how to do this in ConTeXt.

I've been working on a ConTeXt module that provides some elementary AMS-compatible definitions, but for complex equations I have a personal preference for the Nath package in LaTeX, so for multiline you might have more luck using the nath module, which is available on CTAN. There is no manual, but you can use the LaTeX package manual as a reference.

For an example of the sorts of things I end up doing: \begin{equation} \begin{split} \lefteqn{ \frac{\partial (\rho (\phi u)_j)}{\partial t} + \nabla_k (\rho (\phi u)_k u_j) }\quad\quad \\ = &\; -\nabla_j (\phi p) + \nabla_j (\lambda \nabla_k (\phi u_k)) + \nabla_k \left[\mu \left( \nabla_k (\phi u)_j + (\nabla_j (\phi u)_k) \right) \right] \\&\; {} - \lambda (\nabla_j u_k) \nabla_k \phi - \mu (\nabla_k \phi) \nabla_k u_j - \mu (\nabla_k u_k) \nabla \phi_j - \tau_{\text{surface, $jk$}} \nabla_k \phi \end{split} \end{equation}

With ConTeXt+nath, this could become something like \[ \frac{\partial (\rho (\phi u)_j)}{\partial t} + \nabla_k (\rho (\phi u)_k u_j) = \wall -\nabla_j (\phi p) + \nabla_j (\lambda \nabla_k (\phi u_k)) + \nabla_k [\mu ( \nabla_k (\phi u)_j + (\nabla_j (\phi u)_k) )] \\ - \lambda (\nabla_j u_k) \nabla_k \phi - \mu (\nabla_k \phi) \nabla_k u_j - \mu (\nabla_k u_k) \nabla \phi_j - \tau_{\text{surface, $jk$}} \nabla_k \phi \return \] or something.

Looking at that reminds me that I also rather heavily use the \text command from amsmath as well, and rely on its ability to properly size things in subscripts and such. Does this (or an analogue) exist in ConTeXt?

Yes, there is a \text command in ConTeXt provided you use the amsl or nath modules (note that the nath module needs amsl)

Any suggestions? I'd like to be able to simply cut and paste the equations like this one from my LaTeX documents into my ConTeXt documents with as little editing as possible (so that I can maintain consistency between documents in each format), but anything that produces the same output would be good to know about.

Well, if you can use the Nath module in your LaTeX documents (the module is sadly incompatible with much of the AMS features, so there are cases when it's impossible to convert an AMS-LaTeX document to a LaTeX+Nath module) you can do it with ease. Otherwise, some minor corrections will be necessary to reduce the AMS forms into Nath forms; in some cases cleanups are unnecessary (e.g., Nath will accept \left and \right which are not necessary because of its auto-sizing features) so you can often keep an extremely similar syntax for both forms. Do keep in mind, in all this, that the nath package for ConTeXt still has a few edges that needs smoothing, esp. when it comes to arrays, multiline equations and numbering. Hope this helps. -- Giuseppe "Oblomov" Bilotta