在X轴coreplot上使用Epoch时间
有没有办法我可以使用corepolot scatterplot X轴与时代？ 这是我使用的绘图范围。
plotSpace.xRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromFloat(1329375688) length:CPTDecimalFromFloat(100)]; 我正在从文件中读取纪元值。
-(void)plot1{ // Start with some simple sanity checks before we kick off if ( (self.scatterPlotView1 == nil) || (self.graphData == nil)) { NSLog(@"TUTSimpleScatterPlot: Cannot initialise plot without scatterPlotView1 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. CPTTimeFormatter *dateTimeFormatterForXAxis; NSNumberFormatter *formatter = [[NSNumberFormatter alloc] init]; [formatter setMaximumFractionDigits:0]; _graph=[[CPTXYGraph alloc] initWithFrame:CGRectMake(0,500,750,500)]; self.scatterPlotView1.hostedGraph = _graph; // Add some padding to the graph, with more at the bottom for axis labels. self.graph.plotAreaFrame.paddingTop = 20.0f; self.graph.plotAreaFrame.paddingRight = 10.0f; self.graph.plotAreaFrame.paddingBottom = 30.0f; self.graph.plotAreaFrame.paddingLeft= 35.0f; // Tie the graph we've created with the hosting view. self.scatterPlotView1.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]; CPTMutableLineStyle *gridStyle = [CPTMutableLineStyle lineStyle]; CPTMutableLineStyle *plotStyle = [CPTMutableLineStyle lineStyle]; lineStyle.lineColor = [CPTColor redColor]; lineStyle.lineWidth = 2.0f; gridStyle.lineColor = [CPTColor redColor]; gridStyle.lineWidth = 1.0f; plotStyle.lineColor = [CPTColor blackColor]; plotStyle.lineWidth = 1.0; // 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 ellipsePlotSymbol]; plotSymbol.lineStyle = plotStyle; plotSymbol.size = CGSizeMake(2.0, 2.0); // Setup some floats that represent the min/max values on our axis. float xAxisMin = 0; 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(1329375688) length:CPTDecimalFromFloat(500)]; 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.visibleRange =[CPTPlotRange plotRangeWithLocation:CPTDecimalFromDouble(yAxisMin) length:CPTDecimalFromDouble(yAxisMax)]; axisSet.yAxis.visibleRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromDouble(yAxisMin) length:CPTDecimalFromDouble(yAxisMax)]; axisSet.xAxis.title = @"Time(per sec)"; axisSet.xAxis.titleTextStyle = textStyle; axisSet.xAxis.axisLineStyle = lineStyle; axisSet.xAxis.titleOffset = 30.0f; axisSet.xAxis.majorTickLineStyle = lineStyle; axisSet.xAxis.minorTickLineStyle = lineStyle; axisSet.xAxis.majorGridLineStyle = lineStyle; axisSet.xAxis.minorGridLineStyle=gridStyle; axisSet.xAxis.gridLinesRange = axisSet.xAxis.visibleRange; axisSet.xAxis.labelOffset = 6.0f; axisSet.xAxis.majorIntervalLength = CPTDecimalFromFloat(2.0f); axisSet.xAxis.minorTicksPerInterval = 5; axisSet.xAxis.minorTickLength = 10.0f; axisSet.xAxis.majorTickLength = 7.0f; axisSet.xAxis.labelTextStyle = textStyle; axisSet.xAxis.labelFormatter = formatter; axisSet.yAxis.title = @"Uterus Ccontraction"; axisSet.yAxis.titleTextStyle = textStyle; axisSet.yAxis.titleOffset = 20.0f; axisSet.yAxis.axisLineStyle = lineStyle; axisSet.yAxis.majorTickLineStyle = lineStyle; axisSet.yAxis.minorTickLineStyle = lineStyle; axisSet.yAxis.labelTextStyle = textStyle; axisSet.yAxis.labelFormatter = formatter; axisSet.yAxis.majorGridLineStyle= lineStyle; axisSet.yAxis.minorGridLineStyle=gridStyle; axisSet.yAxis.gridLinesRange = axisSet.yAxis.visibleRange; axisSet.yAxis.labelOffset = 3.0f; axisSet.yAxis.majorIntervalLength = CPTDecimalFromFloat(10.0f); 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 = plotStyle; plot.plotSymbol = plotSymbol; //[self.graph reloadData]; [self.graph setNeedsDisplay]; [self.graph addPlot:plot]; } //Delegate method that returns the number of points on the plot -(NSUInteger)numberOfRecordsForPlot:(CPTPlot *)plot { if ( [plot.identifier isEqual:@"mainplot"] ) { return [self.graphData count]; } return 0; } -(NSNumber *)numberForPlot:(CPTPlot *)plot field:(NSUInteger)fieldEnum recordIndex: (NSUInteger)index { if ( [plot.identifier isEqual:@"mainplot"] ) { //NSValue *value = [self.graphData objectAtIndex:index]; //CGPoint point = [value CGPointValue]; if(self.scatterPlotView1){ NSDictionary *entry = [self.graphData objectAtIndex:index]; CGFloat x = [[entry objectForKey:@"X"] floatValue]; CGFloat y = [[entry objectForKey:@"Y"] floatValue]; CGPoint point = CGPointMake(x, y); // FieldEnum determines if we return an X or Y value. if ( fieldEnum == CPTScatterPlotFieldX ) { return [NSNumber numberWithFloat:point.x]; } else // Y-Axis { return [NSNumber numberWithFloat:point.y]; } } else if(self.scatterPlotView2){ NSDictionary *entry = [self.graphData objectAtIndex:index]; CGFloat x = [[entry objectForKey:@"X"] floatValue]; CGFloat z = [[entry objectForKey:@"Y"] floatValue]; CGPoint point1 = CGPointMake(x, z); // FieldEnum determines if we return an X or Y value. if ( fieldEnum == CPTScatterPlotFieldX ) { return [NSNumber numberWithFloat:point1.x]; } else // Y-Axis { return [NSNumber numberWithFloat:point1.y]; } } } return [NSNumber numberWithFloat:0]; }
当我如上所述设置xaxis绘图范围时，我最终得到了一个精简图。 是不是因为我把这个地盘范围当作浮动的呢？
这是一个有效的绘图范围。 没有更多的信息，很难说它是否代表了预期的范围。
关于添加的代码的评论：你在数据源中做了很多不必要的工作。 如果你有很多数据，这将会对你的情节的performance产生不利影响。 尝试这样的事情：
NSDictionary *entry = [self.graphData objectAtIndex:index]; switch ( fieldEnum ) { case CPTScatterPlotFieldX: return [entry objectForKey:@"X"]; break; case CPTScatterPlotFieldY: return [entry objectForKey:@"Y"]; break; }