question: protected double computeMaxYAxisValueLogScale ( double maxValue ) { double v = 0 ; int mantisse = 0 ; int exponent = 0 ; while ( v < maxValue ) { if ( mantisse < 9 ) mantisse ++ ; else { mantisse = 1 ; exponent ++ ; } v = mantisse * Math . pow ( 10 , exponent ) ; } return Math . log10 ( v ) ; }
target:  compute the maximum value on a log scale