BUILDING

For Slackware 14.2 
You need Xbae,plotutils,XmHtml from slackbuilds.org 
and the associated source packages. 
Optionnally, you need Xlt or Sciplot (for nicer graphics). 
Build all the packages and install them with pkgtool before building Oleo.

For Ubuntu 18.04 LTS
Install libmotif-dev, libplot-dev, libxbae-dev, libxmhmtl-dev
Optionally sciplot-dev

With all Linux distributions, you should run the configure script with 
 
./configure  --without-SciPlot --disable-nls (if no Sciplot)
./configure --disable-nls --with-SciPlot-libraries=/usr/lib --with-SciPlot-includes=/usr/include
make 

In the second case, be ready to edit the Makefile in src and change the capitalization -lSciPlot to -lsciplot everywhere if the make fails. 

In both cases, be sure to disable NLS with option --disable-nls.
Internationalization/Localization
in Oleo is full of bugs and you won't be able to enter decimals
or define plots if your locale is not using the '.' as decimal separator. 

If you speak Dutch or French, even with disabled NLS you can still
have the messages in your language by loading the resource file Oleo.nl
or Oleo.fr . 

To avoid all problems caused by non-C locales, run Oleo with LANG=C.

A shell script can be used to run Oleo with the correct parameters.
Example: 

#!/bin/sh

export LANG=C
xrdb -merge Oleo.fr
/usr/local/bin/oleo 

During the build, errors when building the documentation can occur
with the texi2html perl script. Simply do cd doc; cp texi2html.good texi2html.
the ./configure script is generating the texi2html script from texi2html.in
but it contains obsolete instructions. The script texi2html.good is
a corrected version of the script.