IBM Release 1.93 manual

TEMPEST uses the following code for choosing the time step (MAXDIMENSION is 3):

dt=(dx/(C/min_index*sqrt((DOUBLE)(MAXDIMENSION)))) ; period_step=ceil((DOUBLE)((2.0*PI)/(omega*dt))) ;

period_step+=2; i=period_step%4;

if (i!=0) period_step=(period_step+4-i) ;

dt=((2.0*PI)/(omega*(FLOAT)(period_step))) ;

printf("time step after adjustment: %e\n",dt);fflush(stdout);

fprintf(stderr,"period_step: %d\n",period_step);

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