For all of these the non-centrality parameter of the appropriate distribution under the alternative is presented so that one can see how this effect size translates to these terms. There is some relatively extensive documentation on the web. It uses exact and approximate methods to calculate power. The program will calculate effect size under the alternative with some input. The non-centrality parameter of the appropriate distribution under the alternative is presented so that one can see how the effect size translates to these terms.
Documentation comes with the executable.
It uses approximate methods to calculate power. There is pretty extensive documentation. The functions can be pretty general, but documentation is spartan. The functions also provide for computation of the minimum sample size needed to achieve a given level of power. Examples are provided and once you track down the original reference the use is a little more clear.