[ncl-install] Some tips on installing NCL from source code

[Rick Grubin]

All,

Now that it's possible to install NCL from a source code base, we'd  
like to point out a few 'tips and tricks' that have been accumulated  
from building NCL entirely too many times.

To start, please read thoroughly the documentation on how to install  
NCL from source code:
	http://www.ncl.ucar.edu/Download/build_from_src.shtml

There is a lot of information there, as it's not a trivial process to  
build and install even the minimum software necessary to properly  
install NCL.  Some things to note:

   -- When you 'installed' NCL in the past, you were installing a  
precompiled binary with some supporting files.  This means that all
       non-optional software upon which NCL depends was built in to  
the binary.  The base non-optional software may be installed on your
       host; if not, you have to install it prior to building NCL.   
The non-optional software is noted in the documentation, and includes:
             -- netCDF-3
             -- jpeg
             -- zlib
             -- HDF-4

   -- NCL code depends on Fortran blockdata variables being  
initialized correctly.  If you're not sure if your Fortran compiler  
will do this
       correctly, run the tests provided, as noted in the documentation.

   -- There is software functionality that NCL can optionally  
include, if you have it installed or choose to build/install it.   
These software
       packages are noted in the documentation.  If you require any  
of the functionality these provide, you must build/install them.

   -- Installing non-optional and optional software in one location;  
that is, with the same root directory, such as '/usr/local' is a good  
idea if
       you can do so.  It allows you to 'point' to one location when  
referencing libraries, include files and such for building NCL.

   -- When running 'Configure' to set up the NCL build, note that if  
you answer 'y'(es) to building NCL, you must also answer 'y'(es) to
       some of the other questions, in particular those that ask  
about including non-optional software.  Ideally you would not have to  
do this,
       we're looking into modifying the configuration process to  
automatically handle this.

   -- When you run the 'make' process for NCL, be sure to capture the  
output to a log file, as the documentation shows.  It is far easier  
to go
       back and look through a log file for errors if something  
doesn't build correctly.

Please use this list liberally!

----	
Rick Grubin      NCAR/TDD/CISL/VETS
Visualization + Enabling Technologies
grubin at ucar.edu             303.497.1832