Why is my main story X-display on the iPhone?

Question

EDIT: I think my question is better worded like this: How can I have a Y axis that doesn't start from scratch? It seems that the x axis is always placed at y = 0, but I would like the x axis to be on some positive number along the y axis.

Here is a graph with more regular data ... I just want the x axis to be placed with the minimum y value for the graph (about 77) instead of 0.

Here is the function I use to create the chart.

This is a whole bunch of code, and I'm not quite sure which part can be turned off so as not to display the x axis.

Can the displayed x axis have any relationship with my data?

- (void) showGraph:(SavedDetailScreen*)dataSource {

  // create the graph and add it to the view
  CPXYGraph *graph = [[CPXYGraph alloc] initWithFrame: CGRectZero];
  graph.plotArea.masksToBorder = NO;
  CPLayerHostingView *graphView = [[CPLayerHostingView alloc] initWithFrame:CGRectMake(0,0, 280, 240)];
  [self addSubview:graphView];
  graphView.hostedLayer = graph;
  graph.paddingLeft = 50.0;
  graph.paddingTop = 20.0;
  graph.paddingRight = 10.0;
  graph.paddingBottom = 40.0;              

  // set up the ranges for the graph axis
  float minElevation = dataSource.track.tbStats.minAlt;
  float maxElevation = dataSource.track.tbStats.maxAlt-dataSource.track.tbStats.minAlt;
  float minDistance = 0.0f;
  float maxDistance = dataSource.track.tbStats.totalDistance;
  CPXYPlotSpace *plotSpace = (CPXYPlotSpace *)graph.defaultPlotSpace;
  plotSpace.xRange = [CPPlotRange plotRangeWithLocation:CPDecimalFromFloat(minDistance)
                                             length:CPDecimalFromFloat(maxDistance)];
  plotSpace.yRange = [CPPlotRange plotRangeWithLocation:CPDecimalFromFloat(minElevation)
                                                 length:CPDecimalFromFloat(maxElevation)];

  // style the graph with white text and lines
  CPTextStyle *whiteText = [CPTextStyle textStyle];
  whiteText.color = [CPColor whiteColor];              
  CPLineStyle *whiteStyle = [CPLineStyle lineStyle];
  whiteStyle.lineColor = [CPColor whiteColor];
  whiteStyle.lineWidth = 2.0f;

  // set up the axis
  CPXYAxisSet *axisSet = (CPXYAxisSet *)graph.axisSet;      
  CPXYAxis *x = axisSet.xAxis;
  CPXYAxis *y = axisSet.yAxis;              
  x.majorIntervalLength = CPDecimalFromFloat(maxDistance/10.0f);
  x.minorTicksPerInterval = 0;
  x.majorTickLineStyle = whiteStyle;
  x.minorTickLineStyle = whiteStyle;
  x.axisLineStyle = whiteStyle;
  x.minorTickLength = 5.0f;
  x.majorTickLength = 10.0f;
  x.labelOffset = 3.0f;
  x.labelTextStyle = whiteText;
  y.majorIntervalLength = CPDecimalFromFloat(maxElevation/5.0f);
  y.minorTicksPerInterval = 0;
  y.majorTickLineStyle = whiteStyle;
  y.minorTickLineStyle = whiteStyle;
  y.axisLineStyle = whiteStyle;
  y.minorTickLength = 5.0f;
  y.majorTickLength = 10.0f;
  y.labelOffset = 3.0f;
  y.labelTextStyle = whiteText;

  CPScatterPlot *plot = [[[CPScatterPlot alloc] initWithFrame:graph.bounds] autorelease];
  plot.dataLineStyle.lineWidth = 2.0f;
  plot.dataLineStyle.lineColor = [CPColor blueColor];
  plot.dataSource = dataSource;
  [graph addPlot:plot];
  CPPlotSymbol *greenCirclePlotSymbol = [CPPlotSymbol ellipsePlotSymbol];
  greenCirclePlotSymbol.fill = [CPFill fillWithColor:[CPColor greenColor]];
  greenCirclePlotSymbol.size = CGSizeMake(2.0, 2.0);
  plot.plotSymbol = greenCirclePlotSymbol;                 

}

Answer 1

, constantCoordinateValue . x y, .

Answer 2

, , , Decimal . :

graph.axisSet.xAxis.orthogonalCoordinateDecimal = CPDecimalFromFloat(minHeight);

Answer 3

https://github.com/djw/core-plot/tree/9282845bddbb8c40ff314bbfa158beff797c91f7/examples

, isFloatingAxis , , 0.9.

http://code.google.com/p/core-plot/issues/detail?id=125

, , :

x.axisConstraints = [CPTConstraints constraintWithUpperOffset:132];

Answer 4

this structure really needs a better way to tune itself. I do not see problems with the upstart. Maybe just try to simplify the method until debugging becomes manageable. Check the data you go through to make sure that this is what you expect. Even better, create some dummy data that you know will create the plot you expect.