TITLE: A minimal test that DocOnce works
AUTHOR: Hans Petter Langtangen
DATE: Jan 1, 2031

__Summary.__
This is a small document for testing the installation of DocOnce.

!split
TOC: on

!split
======= Test of plain text =======

===== Test standard text with lists and inline tagging =====

Here are some DocOnce features:

  * DocOnce addresses small and large documents containing
    *text with much computer source code and
    LaTeX mathematics*, where the output is desired in different formats
    such as LaTeX, pdfLaTeX, Sphinx, HTML,
    MediaWiki, blogger.com, and wordpress.com.
    A piece of DocOnce text can enter (e.g.) a classical
    science book, an ebook, a web document, and a blog post.
  * DocOnce offers a range of HTML designs, including many
    Bootstrap and Sphinx styles and "solarized color schemes": "https://ethanschoonover.com/solarized".
    A special feature is the many styles for _admonitions_ (boxes for
    warning, notice, question, etc.) in HTML and LaTeX.
  * DocOnce targets in particular large book projects where many different
    pieces of text and software can be assembled in different ways
    and published in different formats for different devices
    (see "example": "https://hplgit.github.io/setup4book-doconce/doc/web/index.html").
  * DocOnce enables authors who write for many times of media
    (blog posts, wikis, LaTeX manuscripts, Sphinx, HTML) to use a common
    source language such that lots of different pieces can easily be
    brought together later to form a coherent (big) document.
  * DocOnce has good support for copying computer code
    directly from the source code files via regular expressions
    for the start and end lines.
  * DocOnce first runs two preprocessors (Preprocess and Mako), which
    allow programming constructs (includes, if-tests, function calls)
    as part of the text. This feature makes it easy to write *one text*
    with different flavors: long vs short text, Python vs Matlab code
    examples, experimental vs mature content.
  * DocOnce can be converted to plain *untagged* text,
    often desirable for email and computer code documentation.
  * DocOnce markup does include tags, so the format is more tagged than
    Markdown, but less than reST, and very much less than
    LaTeX and HTML.
  * Compared to the related tools Sphinx and Markdown, DocOnce
    allows more types of equations (especially systems of
    equations with references), has more flexible
    inclusion of source code, integrates preprocessors, has
    special support for exercises, and produces
    cleaner LaTeX and HTML output.

===== Test of figures and movies =====

Inline figure:

FIGURE: [testfigs/wave1D, width=300, frac=0.7]

Figure ref{fig1} has a caption.

FIGURE: [wave1D/wave1D, width=300, frac=0.7] Figure with caption. label{fig1}

Here is a YouTube movie:

MOVIE: [https://www.youtube.com/embed/P8VcZzgdfSc, width=420, height=315]

MOVIE: [../doc/src/manual/mov/wave.webm, width=700, height=400] Movie on the hard disk: 1D wave motion.

!split
======= Test of math, code, admons, quiz =======

===== Math =====

We have

!bt
\begin{equation}
F = \int_a^b f(x)dx.
\end{equation}
!et

===== Code =====

We can do the integral by

!bc pyshell
>>> from sympy import *
>>> x = 'symbols('x')
>>> f = x*sin(x)*exp(-x)
>>> integrate(f, x(0, 4))
-2*exp(-4)*sin(4) - 5*exp(-4)*cos(4)/2 + 1/2
!ec

Or we can do it numerically via the Trapezoidal rule:

!bc pycod
import numpy

def trapezoidal(f, a, b, n=100):
    """Integrate f from a to b with 100 intervals."""
    x = numpy.linspace(a, b, n+1)
    F = (b-a)/float(n)*(numpy.sum(f(x)) - 0.5*(f(a) + f(b)))
    return F

def f(x):
    return x*numpy.sin(x)*numpy.exp(-x)

print(trapezoidal(f, 0, 4))
!ec

===== Admonitions =====

!bquestion
How do adminitions look like? That depends on the output format and
what type of admon design in the format one has chosen.
!equestion

!bwarning White space is important!
Many DocOnce errors arise from wrong use of white space. The white space
is not as critical as in reStructuredText, but is not ignored either,
as in LaTeX and HTML.
!ewarning
