Installation

Please follow the installation instructions below. If you have problems, refer to the Known problems section. If that doesn’t help to resolve your issue, feel free to contact the developers (see About section).

Prerequisites

The nuflux module requires the following packages:

cfitsio from NASA’s website, https://heasarc.gsfc.nasa.gov/fitsio. Installation instructions are included in the tar ball.
photospline from https://github.com/icecube/photospline. Access to icecube required.
libboost-python-dev obtained via package manager.

Python

Installation via Python3-pip:

pip3 install --user git+https://github.com/icecube/nuflux

If you want to install from a specific branch:

pip3 install --user git+https://github.com/icecube/nuflux.git@<branch>

Build from scratch

If you want to run nuflux from a c++ program, and/or you want to get involved in the nuflux development, it has to be installed with meson and ninja.

git clone https://github.com/icecube/nuflux
cd nuflux
meson build
ninja -C build
sudo ninja -C build install

Known problems

Here are some errors that have been encountered with Python and Meson installation, and the steps taken to resolve them:

photospline and boost are installed in non-standard locations

The Python installation may fail if photospline and boost_python are installed in non-standard locations, e.g. headers in /opt/toolsets/mystuff/include, libraries in /opt/toolsets/mystuff/lib. In this case, set the CMAKE_PREFIX_PATH and BOOST_ROOT environment variables to the root of your toolset installation:
```
CMAKE_PREFIX_PATH=/opt/toolsets/photospline and `BOOST_ROOT`=/opt/toolsets/boost pip install --user git+https://github.com/icecube/nuflux
```
Meson is out of date
```
meson.build:6:0: ERROR: method 'cmake' is invalid
```
The problem here is (most likely) actually not with cmake, but with meson. Try to update meson. On Ubuntu 18.04 for instance, the default meson version is 0.29, which is like half a century old. Remove the old version with the package manager, and get the newest one with Python, like:
```
pip3 install --user meson==0.53
```

Meson is trying to use an old Python

Message: Numpy found: /usr/local/lib/python2.7/dist-packages/numpy/core/include
ERROR: Invalid Boost modules: python27 Run-time dependency Boost (python27) found: NO
meson.build:69:2: ERROR: Dependency "boost" not found

It’s trying to use Python27 while we want to use it with Python3. This a relatively easy fix, just open the meson_options.txt and change the value of the Python option, like:

option('python', type : 'string', value : 'python3', description : 'python path to compile against')

Missing softlink to boost

Error message for Python installation:

/usr/bin/ld: cannot find -lboost_python36

Error message for Meson installation:

Message: Numpy found: /usr/local/lib/python3.6/dist-packages/numpy/core/include
ERROR: Invalid Boost modules: python36 Run-time dependency Boost (python36) found: NO

meson.build:69:2: ERROR: Dependency "boost" not found

For some reason boost seems to be missing, which we clearly installed earlier. The library simply has an unexpected name, so it’s enough to create a softlink, e.g.:

cd /usr/lib/x86_64-linux-gnu/
sudo ln -s libboost_python-py36.so libboost_python36.so