Question

I was wondering how I need to prepare the data so it is ready for core-plot.

• one line per year
• dayOfYear in the x-axis
• value on the y-axis

My x-axis has 366 points (Each day of the year). At the moment I have a dictionary that looks like this

 2009 (year) =     {
        151 (dayofyear) = 5 (value);
        192 = 25;
        206 = 5;
        234 = 20;
        235 = 20;
        255 = 20;
        262 = 10;
        276 = 10;
        290 = 10;
        298 = 7;
        310 = 1;
        338 = 3;
        354 = 5;
        362 = 5;
    };
    2010 =     {
        114 = 7;
        119 = 3;
        144 = 7;
        17 = 5;
        187 = 10;
        198 = 7;
        205 = 10;
        212 = 10;
        213 = 20;
        215 = 5;
        247 = 10;
        248 = 10;
        256 = 10;
        262 = 7;
        264 = 10;
        277 = 10;
        282 = 3;
        284 = 7;
        47 = 5;
        75 = 7;
        99 = 7;
    };
    2011 =     {
        260 = 10;
    };

I think core-plot needs an array doesn’t it? How would you pack this to be the most efficient?

Answer 1

I have actually changed the structure to this.
A dictionary with the year as the key and an array for each point containing the dayofyear and the value.

2009 =     (
                (354,5),
                (338,3),
                (234,20),
                (298,7),
                (192,25)
)

That way the implementation was very easy

-(NSNumber *)numberForPlot:(CPTPlot *)plot field:(NSUInteger)fieldEnum recordIndex:(NSUInteger)index 
{
    return [[[self.data objectForKey:plot.identifier] objectAtIndex: index] objectAtIndex: fieldEnum];
}