public void calcMinTick(){
  if (minData == 0.0)   minTick=0;
 else   minTick=Math.floor(minData / majorTick) * majorTick;
}

public void calcMinTick ( ) { if ( minData == 0.0 ) minTick = 0 ; else minTick = Math . floor ( minData / majorTick ) * majorTick ; }
calculate the optimum minimum tick . override to change default behaviour
