Question

I’m trying to plot two sets of data wrt to time on the same page and hence i need two different X and Y axis. Here is the sample code I’m working with:

 -(void)initialisePlot
{
// Start with some simple sanity checks before we kick off
if ( (self.hostingView == nil) || (self.graphData == nil) ) {
    NSLog(@"TUTSimpleScatterPlot: Cannot initialise plot without hosting view or data.");
    return;
}

if ( self.graph != nil ) {
    NSLog(@"TUTSimpleScatterPlot: Graph object already exists.");
    return;
}

// Create a graph object which we will use to host just one scatter plot.
CGRect frame = [self.hostingView bounds];
self.graph = [[CPTXYGraph alloc] initWithFrame:frame];

// Add some padding to the graph, with more at the bottom for axis labels.
self.graph.plotAreaFrame.paddingTop = 20.0f;
self.graph.plotAreaFrame.paddingRight = 20.0f;
self.graph.plotAreaFrame.paddingBottom = 50.0f;
self.graph.plotAreaFrame.paddingLeft= 20.0f;

// Tie the graph we've created with the hosting view.
self.hostingView.hostedGraph = self.graph;

// If you want to use one of the default themes - apply that here.
[self.graph applyTheme:[CPTTheme themeNamed:kCPTPlainWhiteTheme]];

// Create a line style that we will apply to the axis and data line.
CPTMutableLineStyle *lineStyle = [CPTMutableLineStyle lineStyle];
lineStyle.lineColor = [CPTColor redColor];
lineStyle.lineWidth = 2.0f;

// Create a text style that we will use for the axis labels.
CPTMutableTextStyle *textStyle = [CPTMutableTextStyle textStyle];
textStyle.fontName = @"Helvetica";
textStyle.fontSize = 14;
textStyle.color = [CPTColor blackColor];

// Create the plot symbol we're going to use.
CPTPlotSymbol *plotSymbol = [CPTPlotSymbol hexagonPlotSymbol];
plotSymbol.lineStyle = lineStyle;
plotSymbol.size = CGSizeMake(8.0, 8.0);


// Setup some floats that represent the min/max values on our axis.
float xAxisMin = -10;
float xAxisMax = 10;
float yAxisMin = 0;
float yAxisMax = 100;

// We modify the graph's plot space to setup the axis' min / max values.
CPTXYPlotSpace *plotSpace = (CPTXYPlotSpace *)self.graph.defaultPlotSpace;
plotSpace.xRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromFloat(xAxisMin) length:CPTDecimalFromFloat(xAxisMax - xAxisMin)];
plotSpace.yRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromFloat(yAxisMin) length:CPTDecimalFromFloat(yAxisMax - yAxisMin)];

// Modify the graph's axis with a label, line style, etc.
CPTXYAxisSet *axisSet = (CPTXYAxisSet *)self.graph.axisSet;


axisSet.xAxis.title = @"Data X";
axisSet.xAxis.titleTextStyle = textStyle;
axisSet.xAxis.titleOffset = 30.0f;
axisSet.xAxis.axisLineStyle = lineStyle;
axisSet.xAxis.majorTickLineStyle = lineStyle;
axisSet.xAxis.minorTickLineStyle = lineStyle;
axisSet.xAxis.labelTextStyle = textStyle;
axisSet.xAxis.labelOffset = 3.0f;
axisSet.xAxis.majorIntervalLength = CPTDecimalFromFloat(2.0f);
axisSet.xAxis.minorTicksPerInterval = 1;
axisSet.xAxis.minorTickLength = 5.0f;
axisSet.xAxis.majorTickLength = 7.0f;

axisSet.yAxis.title = @"Data Y";
axisSet.yAxis.titleTextStyle = textStyle;
axisSet.yAxis.titleOffset = 40.0f;
axisSet.yAxis.axisLineStyle = lineStyle;
axisSet.yAxis.majorTickLineStyle = lineStyle;
axisSet.yAxis.minorTickLineStyle = lineStyle;
axisSet.yAxis.labelTextStyle = textStyle;
axisSet.yAxis.labelOffset = 3.0f;
axisSet.yAxis.majorIntervalLength = CPTDecimalFromFloat(20.0f);
axisSet.yAxis.minorTicksPerInterval = 1;
axisSet.yAxis.minorTickLength = 5.0f;
axisSet.yAxis.majorTickLength = 7.0f;

// Add a plot to our graph and axis. We give it an identifier so that we
// could add multiple plots (data lines) to the same graph if necessary.
CPTScatterPlot *plot = [[CPTScatterPlot alloc] init];



plot.dataSource = self;
plot.identifier = @"mainplot";

plot.dataLineStyle = lineStyle;
plot.plotSymbol = plotSymbol;
[_graph reloadData];
[self.graph addPlot:plot];
}

What are the changes that I’m supposed to come up with? Any idea?
Thank you

Answer 1

This line

CGRect frame = [self.hostingView bounds];

means that we will draw our plot on all hostingView.

1. What about use

   -(void)initialisePlot:(UIInteger)indexOfPlot

   instead of:

   -(void)initialisePlot

2. Use just part of hostingView (change frame accordingly indexOfPlot):

   CGRect frame = [self.hostingView bounds]; //change this to:

   Just scheme:

   CGRect frame;

   if (indexOfPlot == 0) {frame = ...(set upper part here)} else {frame = ...(lower)}

3. Then find initialisePlot in source and change to two initialezePlot:0 and initializePlot:1 methods.

Looks rather simple.