Using HMC in Grid version 0.5.1 These are the instructions to use the Generalised HMC on Grid version 0.5.1. Disclaimer: GRID is still under active development so any information here can be changed in future releases. Command line options =================== (relevant file GenericHMCrunner.h) The initial configuration can be changed at the command line using --StartType valid choices, one among these HotStart, ColdStart, TepidStart, CheckpointStart default: HotStart example ./My_hmc_exec --StartType HotStart The CheckpointStart option uses the prefix for the configurations and rng seed files defined in your executable and the initial configuration is specified by --StartTrajectory default: 0 The number of trajectories for a specific run are specified at command line by --Trajectories default: 1 The number of thermalization steps (i.e. steps when the Metropolis acceptance check is turned off) is specified by --Thermalizations default: 10 Any other parameter is defined in the source for the executable. HMC controls =========== The lines std::vector SerSeed({1, 2, 3, 4, 5}); std::vector ParSeed({6, 7, 8, 9, 10}); define the seeds for the serial and the parallel RNG. The line TheHMC.MDparameters.set(20, 1.0);// MDsteps, traj length declares the number of molecular dynamics steps and the total trajectory length. Actions ====== Action names are defined in the file lib/qcd/Actions.h Gauge actions list: WilsonGaugeActionR; WilsonGaugeActionF; WilsonGaugeActionD; PlaqPlusRectangleActionR; PlaqPlusRectangleActionF; PlaqPlusRectangleActionD; IwasakiGaugeActionR; IwasakiGaugeActionF; IwasakiGaugeActionD; SymanzikGaugeActionR; SymanzikGaugeActionF; SymanzikGaugeActionD; ConjugateWilsonGaugeActionR; ConjugateWilsonGaugeActionF; ConjugateWilsonGaugeActionD; ConjugatePlaqPlusRectangleActionR; ConjugatePlaqPlusRectangleActionF; ConjugatePlaqPlusRectangleActionD; ConjugateIwasakiGaugeActionR; ConjugateIwasakiGaugeActionF; ConjugateIwasakiGaugeActionD; ConjugateSymanzikGaugeActionR; ConjugateSymanzikGaugeActionF; ConjugateSymanzikGaugeActionD; ScalarActionR; ScalarActionF; ScalarActionD; each of these action accept one single parameter at creation time (beta). Example for creating a Symanzik action with beta=4.0 SymanzikGaugeActionR(4.0) The suffixes R,F,D in the action names refer to the Real (the precision is defined at compile time by the --enable-precision flag in the configure), Float and Double, that force the precision of the action to be 32, 64 bit respectively.