objective c - Add missing years and corresponding values into arrays -

i've been messing around jbchartview library , seems charting. it's easy enough use i'm having problems getting data in format need particular chart.

the user can enter value , corresponding year. saved using core data. data follows:

year: 0 value: 100 year:2 value 200 year 3 value 150

i create 2 arrays, 1 year number , value. in case though, 3 bars. i'd bar value 0 year 1.

i think best way approach through year array, check see if first value 0, check if every consecutive year value +1. if not, add 1 previous year , insert value of 0 values array @ same index position.

i know if best approach , if doing comparison.

thanks

ok got answer own question , thought i'd post may in future, when creating charts using this, or other libraries.

i first populate 2 mutable arrays

chartlegend = [nsmutablearray arraywithobjects:@1,@3, nil]; chartdata = [nsmutablearray arraywithobjects:@"100",@"300", nil]; 

so i've got years 1 , 3, each associated value in chartdata array.

i need create year 0 , year 2 bar chart has bar every year 0 maximum year, 3.

- (void)additemstoarray {  (int i=0; i<[chartlegend count]; i++) {       //get values our array required calculations     int intpreviousvalue = 0;     int intcurrentvalue = [[chartlegend objectatindex:i]integervalue];      if (i>0)     {         intpreviousvalue = [[chartlegend objectatindex:(i-1)]integervalue];     }        //deal first item in array should 0     if (i == 0)     {         if (intcurrentvalue != 0)         {             [chartlegend insertobject:[nsnumber numberwithint:0] atindex:i];             [chartdata insertobject:[nsnumber numberwithint:0] atindex:i];         }      }      //now deal other array items     else if (intcurrentvalue - intpreviousvalue !=1)     {         int intnewvalue = intpreviousvalue +1;          [chartlegend insertobject:[nsnumber numberwithint:intnewvalue] atindex:i];         [chartdata insertobject:[nsnumber numberwithint:0] atindex:i];     }     }   //create string of values in array nsstring *dates = [chartlegend componentsjoinedbystring:@","]; nsstring *values = [chartdata componentsjoinedbystring:@","];  //display text in couple of labels check intended result self.yearslabel.text = dates; self.valueslabel.text = values; 

}

that seems working me. should easy enough populate arrays using coredata information, make sure it's sorted first.