eiktest - standalone code to test and/or process geometry info ************************************************************** eiktest can read a number of different numerical equilibrium code outputs (EFIT, VMOMS, PPPL Manickam/Menard, or a generic format), or use a Miller local equilibrium, and calculates the various standard quantities needed to do calculations in ballooning coordinates (such as k_perp^2(theta), omega_d(theta), etc.). Numerical or local --> eiktest --> eik*.out --> rungridgen --> grid.out equilibrium (w/ eik.in) (w/ grid.in) These results are then used by GS2, Gryffin, and other codes. Some codes directly read eik.out and don't require running gridgen, though GS2 at present doesn't read eik.out and needs grid.out. *********************************************************** The calculation of the integrals and such for the general geometry for the local equilibrium is done along the theta coordinate that is used in the specification of the R, Z surfaces. The shift to the equal-arc coordinate is done after everything else is calculated. So if there is anything rapidly varying in the original (R, Z, theta) coordinates, it can lead to errors in the geometric coefficients. Thus it may be useful to use large ntheta in eiktest to calculate the ballooning parameters accurately, and then use gridgen to interpolate down to a fewer number of grid points. I believe that Waltz also usually uses an equal poloidal arc lengths Jacobian, with a uniform theta grid spacing. *********************************************************************** Most of the input parameters to eik are also used in gs2. eik_template.in documents some additional parameters. After preparing eik.in, run eiktest. The results will be in eik*.out files. After preparing grid.in, execute "rungridgen". In some cases (perhaps just a local equilibrium), the final line of eik.out will be: ... -8*pi/B_0**2 * dp/drho= and in order for rungridgen to be able to read it, 3 lines need to be added at the end with an editor, to read: ... -8*pi/B_0**2 * dp/drho= 0 0 0 0 0 ******************************************* Further info on plotting or understanding results from eiktest and rungridgen are in eikplot.txt