Unhelpful install instructions

[KingSupernova31]

The README says to run cmake .. -DCMAKE_INSTALL_PREFIX=install -DCMAKE_PREFIX_PATH=path/to/dependencies, but does not specify what dependencies are needed.

[webisu]

Unfortunately installing the various libraries that wgrib2 needs is very system dependent.
I have only built wgrib2 on my Ubuntu system. I had to install software using github,
apt-get and synaptic. The following is from my notes.

--------------- to install iplib -------------------
Install openblas (ubuntu)
$ sudo apt-get install libopenblas-dev

rm -rf $HOME/ip
mkdir $HOME/ip
cd $HOME/ip
----download NCEPLIBS-ip from github (develop branch)
git clone "https://github.com/NOAA-EMC/NCEPLIBS-ip"
cd NCEPLIB-ip
edit CMakeLists.txt
change option(OPENMP "Use OpenMP threading" OFF)
to option(OPENMP "Use OpenMP threading" ON)
mkdir build
cd build
-----------install libaec --------------------
ubuntu: sudo apt install libaec-dev
edit CMakeLists.txt option(USE_AEC "Use AEC?" on)

-----------install openjpeg --------------------
sudo apt install libopenjp2-7-dev

----------install netcdf and hdf4-----
synaptic install libnetcdf-dev .. installs many packages
sudo apt install netcdf-bin * need ncdump to pass wgrib2 tests *

---

png
install libpng by
synaptic libpng-dev png v 1.6

--------- install g2c --------------
export g2c_DIR=/usr/local/NCEPLIBS-g2c/lib/cmake/g2c

cmake -DCMAKE_INSTALL_PREFIX=$HOME/ip ..
make

do not do "make -j(some integer)"

make test
(sudo) make install

----- Caution -----------------
If someone did a "root build", the ip build will be in /usr/local
This will over ride the "user build"!
So a user cannot install a newer version of ip!

After you have installed the library, Now to build wgrib2
need to get wgrib2

git clone [email protected]:NOAA-EMC/wgrib2.git
cd wgrib2
ex enable netcdf
edit CMakeLists.txt option(USE_NETCDF "Use NetCDF?" on)
enable AEC
edit CMakeLists.txt option(USE_AEC "Use AEC?" off)
enable openjpeg
edit CMakeLists.txt option(USE_OPENJPEG "Use NetCDF?" on)
enable ipolates
edit CMakeLists.txt option(USE_IPOLATES "Use Ipolates" on)
(comments may have changed)

mkdir build
cd build
export g2c_DIR=/usr/local/NCEPLIBS-g2c/lib/cmake/g2c
cmake ..
cmake .. -DCMAKE_BUILD_TYPE=Release
make
make test

parallel build
make -jN
make -jN test
(sudo) make install

[edwardhartnett]

OK, so how can we make this better?

• We could release ip/g2c into the ubuntu package management system. This is not hard, IIRC.
• Apparently parallel make builds did not work for you on g2c? In such cases it's important to capture output and open an issue. We can make sure this works.
• We could release wgrib2 as an ubuntu package?

[webisu]

Installing ip was easy once you knew to install openblas-dev and the URL of ip. Installing g2c was a pain because you need to compile Jasper. Getting Jasper going was a difficult because you need 11 options to get the Cmake to work. If it were documented that g2c could use OpenJPEG,' I could have saved much time. Installing netcdf was easy using synaptic.

…

On Mon, Jan 13, 2025 at 3:31 PM Edward Hartnett ***@***.***> wrote: OK, so how can we make this better? - We could release ip/g2c into the ubuntu package management system. This is not hard, IIRC. - Apparently parallel make builds did not work for you on g2c? In such cases it's important to capture output and open an issue. We can make sure this works. - We could release wgrib2 as an ubuntu package? — Reply to this email directly, view it on GitHub <#306 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AEIB7ZTN2V3ZEHT2KORVT3D2KQPB7AVCNFSM6AAAAABUZGGIMOVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDKOBYGEZTIMBXGU> . You are receiving this because you commented.Message ID: ***@***.***>

[mzuranski]

Chiming in with my two cents: If wgrib2 were available in apt for Ubuntu, that would make me sooo happy. My question there would be how it would handle various options; e.g. IPLOATES is optional but I need it for my applications, would this be enabled in the apt version?

I'm installing this now for the first time since moving to Cmake and to be honest the new workflow surrounding ip/g2c is giving me a learning curve. apt install wgrib2 would be marvelous for those less experienced with compiling software.