Measured times on various platforms

The program execution time depends on the number of patches and the number of wire segments used. The central processor time approximately follows the formula;

- T=
- T
_{1}+ T_{2}+ T_{3}+ T_{4} - T
_{1}=(A_{1}kN_{s}^{2}+ A_{2}kN_{s}^{2}+ A_{3}kN_{s}N_{p}+ A_{4}N_{c})/M, - T
_{2}=B(N_{s}+ 2N_{p})^{3}/M_{2}, - T
_{3}=CN_{s}+2N_{p})^{2}/M , - T
_{4}=DkN_{f}(N_{s}+2N_{p}), - where
- N
_{s}=number of wire segments, - N
_{p}=number of surface Patches, - N
_{c}=number of connections between a wire and surface, - N
_{e}=number of different excitations, - N
_{f}=number of far-field calculation points - M=number of degrees of symmetry,
- k=
- 1 for structure in free space,
- 2 for perfect ground of reflection coefficient approximation, and
- 4 for Sommerfeld/Norton method. T
_{1}is the time to fill the interaction matrix; T_{2}is the time to factor the matrix; T_{3}is the time to solve for the currents for all excitations; and T_{4}is the time to calculate far fields.The proportionality factors depend on the computer system on which the program is run. The factors in seconds for a CDC 7600 computer when the matrix fits in core are roughly

- A
_{1}=3.(10^{-4}), - A
_{2}=5.(10^{-5}), - A
_{3}=5.(10^{-4}), - A
_{4}=2.(10^{-2}), - B=2.(10
^{-6}), - C=4.(10
^{-6}), and - D=6.(10
^{-5}), When the extended thin-wire kernel is used, A_{1}is increased by about 18 percent. If the approximation for large interaction distances is used with RKH=R_{o}, then A_{1}is multiplied by (1 - 0.7F) where F is the faction of all segment pairs for which the separation is grater than R_{o}.Unless a large number of excitations or far fields are requested, T

_{1}and T_{2}will account for nearly all of the running time. If the matrix does not fit in core storage, T_{1}and T_{2}will be larger than indicated above. They may be much larger if I/O time is included.The code SOMNEC requires about 15 sec to write the Summerfeld/Norton data file on a CDC 7600 computer.