At present, there is no supported standard installation process.

Building and running with docker:

The quickest way to build and run NGEN is to follow what we do for our model run testing:

First we make a new directory: mkdir ngen && cd ngen

Then clone the github repository: git clone https://github.com/NOAA-OWP/ngen.git

Then we can build with docker: docker build . --file ./docker/CENTOS_NGEN_RUN.dockerfile --tag localbuild/ngen:latest

Building manually:

Install the Linux required packages (package names shown for Centos 8.4.2105):

yum install tar git gcc-c++ gcc make cmake python38 python38-devel python38-numpy bzip2 udunits2-devel texinfo

Clone the NGen repository:

git clone https://github.com/NOAA-OWP/ngen

cd ngen

Download the Boost Libraries:

curl -L -o boost_1_79_0.tar.bz2 https://sourceforge.net/projects/boost/files/boost/1.79.0/boost_1_79_0.tar.bz2/download \
    && tar -xjf boost_1_79_0.tar.bz2 \
    && rm boost_1_79_0.tar.bz2

Set the ENV for Boost and C compiler:

set BOOST_ROOT="/boost_1_79_0"

set CXX=/usr/bin/g++

Get the git submodules:

git submodule update --init --recursive -- test/googletest

git submodule update --init --recursive -- extern/pybind11

Configure NGen using cmake:

In addition to normal CMake options, the following ngen configuration options are available:

Option	Description
NGEN_WITH_NETCDF	Include NetCDF support
NGEN_WITH_SQLITE3	Include SQLite3 support (GeoPackage support)
NGEN_WITH_UDUNITS	Include UDUNITS support
NGEN_WITH_MPI	Include MPI (Parallel Execuation) support
NGEN_WITH_BMI_FORTRAN	Include Fortran BMI support
NGEN_WITH_BMI_C	Include C BMI support
NGEN_WITH_PYTHON	Include Python support
NGEN_WITH_ROUTING	Include `t-route` integration
NGEN_WITH_TESTS	Include unit and integration tests
NGEN_QUIET	Include suppressing unwanted message output

‍These can be included by adding -D{Option:BOOL}=[ON/OFF] to the following CMake command.

‍Note: if -DNGEN_WITH_PYTHON:BOOL=ON, and you are using an activated virtual environment, then CMake will bind its Python configuration to your virtual environment. This means, when you run the ngen executable, your virtual environment must be activated.

The following CMake command will configure the build:

cmake -DCMAKE_CXX_COMPILER=/usr/bin/g++ \
      -DBOOST_ROOT=boost_1_79_0 \
      -B /build \
      -S .

Build NGen using cmake:

cmake --build build --target ngen

If you want to build with multiple jobs (in parallel), then you can run the following instead:

# replace 2 with number of jobs

cmake --build build --target ngen -- -j 2

Running the Model:

./build/ngen data/catchment_data.geojson all data/nexus_data.geojson all data/example_realization_config.json

Further information on each step:

Make sure all necessary dependencies are installed, and then build the main ngen target with CMake. Then run the executable, as described here for basic use or here for distributed execution. A step by step instruction and install with more options are also provided on our wiki page.