atlc, which is part of the atlc package of programs, can be quite CPU intensive. This is especially troublesome if atlc is executed a large number of times in an itterative loop, as the program desgin_coupler will do if asked to find the phyical dimensions of a directional coupler. To reduced execution time, the program atlc could (until release 4.5.1) be configured to support multiple processors This obviously requires a computer with more than one CPU.
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