Problem: Linking numpy to correct Linear Algebra libraries. Process is so complicated that I might be looking for the solution 6th time and I have no idea whats going wrong. I am on Ubuntu 12.04.5. I reinstalled blas and lapack and then reinstalled numpy using pip. I did that in system environment and then also tried in virtualenv environment. None of the things seem to be working.

Here is my numpy.__config__.show():

lapack_info:NOT AVAILABLE
lapack_opt_info:NOT AVAILABLE
openblas_lapack_info:NOT AVAILABLE
blas_info:NOT AVAILABLE
atlas_3_10_blas_threads_info:NOT AVAILABLE
atlas_threads_info:NOT AVAILABLE
blas_src_info:NOT AVAILABLE
atlas_3_10_threads_info:NOT AVAILABLE
atlas_blas_info:NOT AVAILABLE
atlas_3_10_blas_info:NOT AVAILABLE
lapack_src_info:NOT AVAILABLE
atlas_blas_threads_info:NOT AVAILABLE
openblas_info:NOT AVAILABLE
blas_mkl_info:NOT AVAILABLE
blas_opt_info:NOT AVAILABLE
atlas_info:NOT AVAILABLE
atlas_3_10_info:NOT AVAILABLE
lapack_mkl_info:NOT AVAILABLE
mkl_info:NOT AVAILABLE

This is a very common error and has lots of solution depending on the user's environment and history. I recently went through the whole process of installing BLAS and LAPACK as instructed here: https://stackoverflow.com/a/9173550/3413239. I was able to successfully install both.

However, I initially had these libraries: (ls /usr/lib | grep blas)

libopenblas.so.0
openblas-base/
libblas.so.3gf
libblas.3

How should I link my numpy to linear algebra libraries. Is it mandatory to have all the linaear algebra libraries? i.e. lapack, blas, atlas?

I am assuming once the numpy is linked all other modules like scipy and Orange will work.

It's possible that you have unmet dependencies. When I had this error, I was able to fix it by installing two packages:

sudo apt-get install libblas-dev  liblapack-dev