I'm trying to embed python with numpy in a C++ application. I'm using Windows 10 and Visual Studio 2015. Currently I have Anaconda and WinPython installed (because I'm using Python scripts that work only with one or the other). I don't have any environment variable related to python.
For my C++ application, I'm using the WinPython python, that have numpy and a handful of other packages installed. I managed to embed python and numpy in my application when using Visual studio, both for Debug and Release. Everything is working, python is initialized and I can use numpy array and functions. WinPython is correctly used. As a simple test in my code I have:
_putenv_s("PYTHONPATH", ".");
Py_InitializeEx(0);
PyRun_SimpleString("import sys");
PyRun_SimpleString("print(sys.path)");
PyRun_SimpleString("print(sys.prefix)");
PyRun_SimpleString("print(sys.executable)");
PyRun_SimpleString("import importlib.machinery");
PyRun_SimpleString("print(importlib.machinery.all_suffixes())");
init_numpy2();
That prints:
['C:\\DevC++\\Tesseler-Cmake\\build', 'C:\\Git\\WPy64-3741\\python-3.7.4.amd64\\python37.zip', 'C:\\Git\\WPy64-3741\\python-3.7.4.amd64\\DLLs', 'C:\\Git\\WPy64-3741\\python-3.7.4.amd64\\lib', 'C:\\DevC++\\Tesseler-Cmake\\build\\Release', 'C:\\Git\\WPy64-3741\\python-3.7.4.amd64', 'C:\\Git\\WPy64-3741\\python-3.7.4.amd64\\lib\\site-packages', 'C:\\Git\\WPy64-3741\\python-3.7.4.amd64\\lib\\site-packages\\win32', 'C:\\Git\\WPy64-3741\\python-3.7.4.amd64\\lib\\site-packages\\win32\\lib', 'C:\\Git\\WPy64-3741\\python-3.7.4.amd64\\lib\\site-packages\\Pythonwin']
C:\Git\WPy64-3741\python-3.7.4.amd64
C:\DevC++\Tesseler-Cmake\build\Release\Tesseler.exe
['.py', '.pyw', '.pyc', '.cp37-win_amd64.pyd', '.pyd']
I then set-up an installer using Wix in Release, and checked that the Winpython python37.dll is shipped with my application. But when I run my program, I'm getting this error when calling import_numpy2():
['C:\\Tesseler', 'C:\\Tesseler\\python37.zip', 'C:\\Users\\Florian\\anaconda3\\Lib', 'C:\\Users\\Florian\\anaconda3\\DLLs', 'C:\\Users\\Florian\\anaconda3', 'C:\\Users\\Florian\\anaconda3\\lib\\site-packages', 'C:\\Users\\Florian\\anaconda3\\lib\\site-packages\\win32', 'C:\\Users\\Florian\\anaconda3\\lib\\site-packages\\win32\\lib', 'C:\\Users\\Florian\\anaconda3\\lib\\site-packages\\Pythonwin']
C:\Users\Florian\anaconda3
C:\Tesseler\Tesseler.exe
['.py', '.pyw', '.pyc', '.cp37-win_amd64.pyd', '.pyd']
ModuleNotFoundError: No module named 'numpy'
I don't understand why anaconda is added to the sys.path and sys.prefix since I never have any reference to it in my visual studio project, nor any environment variable referencing it. I see why using a dll from anaconda could lead to some problem but I checked with Process Explorer that my application is using the python37.dll shipped with it, which is the case. Any idea what could cause this error?
Update:
Following ideas described in this thread, I managed to make it work by creating a python subfolder and copying the whole numpy, scipy, pandas and statsmodels folders in it (these 4 modules are needed by my script). These folders were copied from C:\Git\WPy64-3741\python-3.7.4.amd64\Lib\site-packages. I also added this python subfolder to PYTHONPATH: _putenv_s("PYTHONPATH", ".;./python");
Anyway, if someone has a better solution I'm eager to hear it as I find it annoying to have to bundle these modules (more than 600 Mo) when my application is roughly 20 Mo...
