Printac prints the value of the specified AUTO constant on screen.
printac [-h] (runrfile-) ac_name |
-h | : | Display a usage message and exit with nonzero return value. |
run | : | Read constants of run with qualified run name run. | ||||
rfile | : | Read constants from r.*-file rfile. | ||||
- | : | Read constants from standard input. | ||||
ac_name | : | NDIM NTST NCOL NMX NPR RL0 RL1 A0 A1 | ||||
EPSL EPSU EPSS DS DSMIN DSMAX |
Printac prints on screen the value that was assigned to an AUTO constant during the run with qualified run name run. This might be useful for initializing certain computations, for example, if you want to compute a cascade of period-doubling bifurcations. If you use the bash, then a command like
rauto name run rrun -IRS $(splabs rrun PD 1 1) \ | ||
-NTST $(( $(printac rrun NTST)*2 )) -ISW -1 ... |
will initialize the computation of a doubled solution with twice the number of mesh points of the single solution. Note that you might also want to decrease the initial step size. You need to use the desktop calculator dc for that (again bash notation):
h0=$(printac rrun DS) | ||
h0=$(dc -e "8 k 0 1 $h0 * 4.67 / p") | ||
rauto ... -DS $h0 ... |
Set DSMIN to a sufficiently small value. Note that we have to go to some length here to deal with negative values of DS.
Printac returns 0 on success and 1 if an error occurred or the -h switch was given.