question: public void calcMaxTick ( ) { if ( maxData == 0 ) { maxTick = 0 ; } else if ( maxData < 0.0 ) { maxTick = - Math . floor ( - maxData / majorTick ) * majorTick ; } else { maxTick = Math . ceil ( maxData / majorTick ) * majorTick ; } }
target:  Calculate the optimum maximum tick. Override to change default behaviour