Core Plot causing crash on device but not simulator

I'm using core plot to create a small plot in one of my view controllers. I have been pulling my hair out trying to track down this error. I install on the simulator and it works fine but as soon as I put it on my device I get the following error:

2010-02-04 22:15:37.394 Achieve[127:207] *** -[NSCFString drawAtPoint:withTextStyle:inContext:]: unrecognized selector sent to instance 0x108530
2010-02-04 22:15:37.411 Achieve[127:207] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '*** -[NSCFString drawAtPoint:withTextStyle:inContext:]: unrecognized selector sent to instance 0x108530'
2010-02-04 22:15:37.427 Achieve[127:207] Stack: (
    843263261,
    825818644,
    843267069,
    842763033,
    842725440,
    253481,
    208187,
    823956912,
    823956516,
    823956336,
    823953488,
    823952500,
    823985628,
    842717233,
    843010887,
    843009055,
    860901832,
    843738160,
    843731504,
    8797,
    8692
)
terminate called after throwing an instance of 'NSException'
Program received signal:  “SIGABRT”.

Debugger Output (as requested):

#0  0x33b3db2c in __kill
#1  0x33b3db20 in kill
#2  0x33b3db14 in raise
#3  0x33b54e3a in abort
#4  0x33c5c398 in __gnu_cxx::__verbose_terminate_handler
#5  0x313918a0 in _objc_terminate
#6  0x33c59a8c in __cxxabiv1::__terminate
#7  0x33c59b04 in std::terminate
#8  0x33c59c2c in __cxa_throw
#9  0x3138fe5c in objc_exception_throw
#10 0x32433bfc in -[NSObject doesNotRecognizeSelector:]
#11 0x323b8b18 in ___forwarding___
#12 0x323af840 in __forwarding_prep_0___
#13 0x0003de28 in -[CPTextLayer renderAsVectorInContext:] at
CPTextLayer.m:117
#14 0x00032d3a in -[CPLayer drawInContext:] at CPLayer.m:146
#15 0x311c95b0 in -[CALayer _display]
#16 0x311c9424 in -[CALayer display]
#17 0x311c9370 in CALayerDisplayIfNeeded
#18 0x311c8850 in CA::Context::commit_transaction
#19 0x311c8474 in CA::Transaction::commit
#20 0x311d05dc in CA::Transaction::observer_callback
#21 0x323ad830 in __CFRunLoopDoObservers
#22 0x323f5346 in CFRunLoopRunSpecific
#23 0x323f4c1e in CFRunLoopRunInMode
#24 0x335051c8 in GSEventRunModal
#25 0x324a6c30 in -[UIApplication _run]
#26 0x324a5230 in UIApplicationMain
#27 0x0000225c in main at main.m:14

Here is my viewDidLoad method:

- (void)viewDidLoad 
{
    [super viewDidLoad];
    self.view.backgroundColor = [[UIColor alloc] initWithPatternImage:[UIImage imageNamed:@"bg.png"]];
    [self loadData];

    self.graph = [[CPXYGraph alloc] initWithFrame: self.plotView.frame];

    CPLayerHostingView *hostingView = self.plotView;
    hostingView.hostedLayer = graph;
    graph.paddingLeft = 50;
    graph.paddingTop = 10;
    graph.paddingRight = 10;
    graph.paddingBottom = 10;

    percentFormatter = [[NSNumberFormatter alloc] init];
    [percentFormatter setPercentSymbol:@"开发者_Python百科%"];
    [percentFormatter setNumberStyle:NSNumberFormatterPercentStyle];
    [percentFormatter setLocale: [NSLocale currentLocale]];
    [percentFormatter setMultiplier:[NSNumber numberWithInt:1]];
    [percentFormatter setMaximumFractionDigits:0];

    CPXYPlotSpace *plotSpace = (CPXYPlotSpace *)graph.defaultPlotSpace;

    plotSpace.xRange = [CPPlotRange plotRangeWithLocation:CPDecimalFromFloat(0)
                                                   length:CPDecimalFromFloat(maxX)];
    plotSpace.yRange = [CPPlotRange plotRangeWithLocation:CPDecimalFromFloat(minY) 
                                                   length:CPDecimalFromFloat(maxY-minY)];

    CPLineStyle *lineStyle = [[CPLineStyle lineStyle]retain];
    lineStyle.lineColor = [CPColor grayColor];
    lineStyle.lineWidth = 1.0f;

    CPTextStyle *whiteText = [CPTextStyle textStyle];
    whiteText.color = [CPColor whiteColor];    

    CPXYAxisSet *axisSet = (CPXYAxisSet *)graph.axisSet;

    //  axisSet.xAxis.majorIntervalLength = [[NSDecimalNumber decimalNumberWithString:@"0"]decimalValue];
    axisSet.xAxis.minorTicksPerInterval = 0;
    axisSet.xAxis.majorTickLineStyle = nil;
    axisSet.xAxis.minorTickLineStyle = nil;
    axisSet.xAxis.axisLineStyle = lineStyle;
    axisSet.xAxis.minorTickLength = 0;
    axisSet.xAxis.majorTickLength = 0;
    axisSet.xAxis.labelFormatter = nil;
    axisSet.xAxis.labelTextStyle = nil;

    axisSet.yAxis.majorIntervalLength = [[NSDecimalNumber decimalNumberWithString:intY]decimalValue];
    axisSet.yAxis.minorTicksPerInterval = 5;
    axisSet.yAxis.majorTickLineStyle = lineStyle;
    axisSet.yAxis.minorTickLineStyle = lineStyle;
    axisSet.yAxis.axisLineStyle = lineStyle;
    axisSet.yAxis.minorTickLength = 2.0f;
    axisSet.yAxis.majorTickLength = 4.0f;
    axisSet.yAxis.labelFormatter = percentFormatter;
    axisSet.yAxis.labelTextStyle = whiteText;

    CPScatterPlot *xSquaredPlot = [[[CPScatterPlot alloc]initWithFrame:graph.defaultPlotSpace.graph.bounds] autorelease];
    xSquaredPlot.identifier = @"Plot";
    xSquaredPlot.dataLineStyle.lineWidth = 4.0f;
    xSquaredPlot.dataLineStyle.lineColor = [CPColor yellowColor];
    xSquaredPlot.dataSource = self;
    [graph addPlot:xSquaredPlot];

}

Any help would be appreciated!

-drawAtPoint:withTextStyle:inContext: is a category method added to NSString in CPTextStyle.h.

In order for category methods to be used with a static library like Core Plot on the iPhone, you will need to add -ObjC to your Other Linker Flags in your project's build settings. Under iPhone OS 3.0, you might also need to add -all_load to your Other Linker Flags to prevent exceptions like the one you're seeing.

This is documented in the instructions for using Core Plot within applications.

Add to you project the framework/ iPhoneOnly directory from the CorePlot source tree.

i got it working fine by adding the -all_load -ObjC flag in the Target>Settings. I think this is where everyone is getting confused.