depends on gnu scientific library (gsl), which has dependancies on blas. Build like: gcc -lgsl -lm -o cpw cpw.c Formula from: https://chemandy.com/calculators/coplanar-waveguide-with-ground-calculator.htm Example run: $ ./cpw Name cpw - calculate impedance of a coplanar waveguide Usage: test2 thickness clearance h er $ ./cpw 2.5 3 1.5 4.2 53.3415029836