Lightgbm OSError, Library not loaded

Question

If I simply do:

import lightgbm as lgb

I\'m getting

python script.py 
Traceback (most recent call last):
File \"script.py\", li         


        

Answer 1

Same error, different source: seems like I had the gcc 8 version installed, and it needs gcc 7.

It worked by switching it back to last gcc 7 version:

brew switch gcc 7.3.0_1

Answer 2

On MacOS High Sierra with MacPorts installed, I did the following:

1. Install clang-5.0 using MacPorts
2. Inside the /build directory, run cmake -DCMAKE_CXX_COMPILER=clang++-mp-5.0 -DCMAKE_C_COMPILER=clang-mp-5.0 ..
3. To build the python package, go to /python_package directory and modify the setup.py script. You need to modify the function compile_cpp() at the very end that checks the case for other OS (including Mac). Before the silent_call(...), add the following two lines: cmake_cmd.append("-DCMAKE_CXX_COMPILER=clang++-mp-5.0") cmake_cmd.append("-DCMAKE_C_COMPILER=clang-mp-5.0")
4. Run sudo python setup.py install. Enjoy

Answer 3

I used this command generated from PyCharm and it worked for me.

conda install -p { < =replace with USER_HOME_DIR>}/anaconda3 lightgbm -y

Note : i tried Brew and pip install but they didn't work for me as Azure ML studio already downloaded other versions of LightGBM that were causing conflict in upgrading to correct packages.

Answer 4

For users with macports, replace the beginning of the brew solution with:

1. port install gcc7 cmake
2. export CXX=g++-mp-7 CC=gcc-mp-7

Answer 5

All the above answers didn't work for me. On Mac, if I installed the libomp using brew fixed the problem: Refer: link

brew install libomp

Answer 6

I find a similar problem here LightGBM
The answer and comment may help you.

Build LightGBM in Mac:

brew install cmake  
brew install gcc --without-multilib  
git clone --recursive https://github.com/Microsoft/LightGBM ; cd LightGBM  
mkdir build ; cd build  
cmake ..   
make -j  

Then install:

cd ../python-packages  
sudo python setup.py install --precompile

As stated by @ecodan, you might need to force Mac to use GCC and G++ instead of the default compiler. So instead of building with cmake .., try:

cmake -DCMAKE_C_COMPILER=/usr/local/Cellar/gcc/6.1.0/bin/gcc-6 -DCMAKE_CXX_COMPILER=/usr/local/Cellar/gcc/6.1.0/bin/g++-6 ..

ajusting the versions to match yours.