# 2023-08-11
#
# Compiling Octave (an oldish one that we happened to have) for Raspberry Pi .. in fact, a Raspberry Pi Zero W
# 
# Wanted a minimal one for command-based interaction with data - no need even for plotting.
# This record is in case needed packages, configure-options, or reminder of swap-requirement are needed on another such occasion.


# increase swap, from the default 100 MB
# without this, the compilation was killed for out-of-memory after 5h or so
#
vi /etc/dphys-swapfile   # increase size to 2048 [MiB](as 32-bit system max, supposedly)
/etc/init.d/dphys-swapfile restart   # activate
free       
 	Mem:     429    
 	Swap:   2047 

# add compiler + libraries required for the build 
# 
apt install gfortran
apt install libblas-dev 
apt install liblapack-dev
apt install libpcre++-dev libpcre2-dev 
apt install libreadline-dev readline-common    # optional 

# get and unpack source
# 
ssh 10.1.1.1 cat /home/public/sfw/unix_progs/octave/octave-5.1.0.tar.xz | xzcat -d | tar -xpf -
cd octave-5.1.0

# configure with pretty-near nothing optional enabled (readline, and pcre since pcre is needed for the build anyway) 
# 
./configure --prefix=/opt/octave/5.1.0 --enable-readline --enable-dependency-tracking --disable-option-checking --disable-largefile --disable-threads --disable-64 --disable-atomic-refcount --disable-openmp --disable-libtool-lock --disable-no-undefined --disable-cross-tools --disable-rpath --disable-jit --disable-fftw-threads --disable-java --disable-docs --disable-hg-id --disable-qhull --enable-pcre --without-z --without-bz2 --without-hdf5 --without-fftw3 --without-fftw3f --without-glpk --without-curl --without-sndfile --without-portaudio --without-x --without-framework-carbon --without-opengl --without-framework-opengl --without-freetype --without-fontconfig --without-q --without-qscintilla --without-fltk --without-qrupdate --without-suitesparseconfig --without-amd --without-camd --without-colamd --without-ccolamd --without-cholmod --without-cxsparse --without-umfpack --without-klu --without-sundials_nvecserial --without-sundials_ida --without-arpack

# 
make 






# note ... the following is after already several hours of compilation that was stopped 
# when it ran out of memory (with about 450MB RAM and the default Raspbian 100MB swap)
# 5 hours into the work; so it then, with 2048MB swap, took some 11h more to finish off! 
# swap useage went up to nearly 1GB at the peak (logged each few seconds) 

Octave successfully built.  Now choose from the following:
   ./run-octave    - to run in place to test before installing
   make check      - to run the tests
   make install    - to install (PREFIX=/opt/octave/5.1.0)
   HG ID for this build is "hg-id-disabled"

real    670m50.592s
user    539m44.209s
sys     25m26.695s