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This directory contains examples for the 'chem' language.

You can view the graphical display of the examples by calling

    @g@chem <file> | groff -p ...

On the displays, you can see rings consisting of several lines and
bonds (lines).  All points on rings and bonds that do not have a
notation mean a C atom (carbon) filled with H atoms (hydrogen) such
that the valence of 4 is satisfied.

For example, suppose you have just a single line without any
characters.  That means a bond.  It has two points, one at each end of
the line.  So each of these points stands for a C atom, the bond
itself connects these 2 C atoms.  To fulfill the valence of 4, each
points has to carry additionally 3 H atoms.  So the single empty bond
stands for CH3-CH3, though this combination doesn't make much sense
chemically.


####### License

Copyright (C) 2006-2018 Free Software Foundation, Inc.
Written by Bernd Warken <groff-bernd.warken-72@web.de>.

This file is part of 'chem', which is part of 'groff'.

'groff' is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

'groff' is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
for more details.

The GPL2 license text is available in the internet at
<http://www.gnu.org/licenses/gpl-2.0.html>.


##### Editor settings
Local Variables:
fill-column: 72
mode: text
End:
vim: set textwidth=72: