How to let octave use more CPU?

I am using octave under debian. Everything is working ok. I would like the octave-programs to finish faster. My "CPU usage monitor"-icon (LXDE) shows that, while octave is calculating, only about one third of my CPU is used. Is there a way to configure the system to use more CPU for octave's calculations? **-- UPDATE --** Extra info: Looking at htop as my program run I have the following: 0. the CPU has 4 cores and 7.71GiB RAM. 1. from the beginning until before plotting, one core (apparently random selected) is used at 100% and the others at below 2%. 2. after plotting begins, another core (apparently also random selected, sometimes the same) is used to 100% and the other ones kept below 2%. 3. there is a little change in MEM usage (max difference ~0.1GiB). 4. there is no change in swap.