This version of the code is deprecated and is kept purely for historical reasons. It uses ctypes to link C code for computing the tables of Ylm and accumulating the sums to get alm. If you wish to use this version and you have the GNU C compiler installed as "gcc" then you should be able to simply type "make" in this directory to generate "sht_helper.so" and then import the "sht.py" class as a drop-in replacement for the version in the "sht" directory of the main repo.