从命令行安装 python package 时出错

Question

I'm trying to efficiently code quantum mechanical time-evolution which requires me to exponentiate Hamiltonian matrices that are very large but very sparse. To do this, I have been trying to install the expokit python wrapper ( https://github.com/weinbe58/expokitpy ) but am running into issues. I am on Mac and once I download the files and run python setup.py install the terminal runs through an installation process but then returns

xcrun: error: invalid active developer path (/Library/Developer/CommandLineTools), missing 
xcrun at: /Library/Developer/CommandLineTools/usr/bin/xcrun
xcrun: error: invalid active developer path (/Library/Developer/CommandLineTools), missing 
xcrun at: /Library/Developer/CommandLineTools/usr/bin/xcrun
error: Command "/usr/local/bin/gfortran -Wall -g -ffixed-form -fno-second-underscore -fPIC -O3 -funroll-loops -I/opt/anaconda3/lib/python3.7/site-packages/numpy/core/include -c -c ./expokit/lapack.f -o build/temp.macosx-10.9-x86_64-3.7/expokit/lapack.o" failed with exit status 

This is my first time installing a package not using pip install and I can't figure out what's going on here. Any help is much appreciated!

PS if anyone knows a better package that I should be using, please let me know too!

Answer 1

This is not a problem with python, your xcode not installed properly (or missing permissions or something).

xcode-select --install

Will probably fix it. For more info, look at this article

Also, why not just use scipy? Scipy provides the same functionality, and will probably work better for you if you're already using numpy/scipy. See docs