Computer Resource Usage

e-LBOW uses an increasing amount of computer memory as the number of atoms in the molecule increases. From a minimum of about 32 megabytes the memory usage approaches 1 gigabyte for approximately 280 non-hydrogen atoms. This is shown in the graph below. The memory usage is approximately a quadratic function of the number of non-hydrogen atoms.

The computer time also increases with atom number. The portion wholely written in Python which excludes the AM1 calculation is a quadratic function and takes about 10 minutes for a 200 non-hydrogen atom molecule on an Athlon running Fedora Core 3.

The AM1 calculation which is written in c++ for speed has a cubic relationship to the number of atoms. This is diplayed in the graph below along with the total time. The total time for a 100 non-hydrogen atom molecule is 25 minutes.