核心情节不是scalling

Question

I cannot get my graph with all the plot points to fit in my view.

The coordinates being displayed in the screen shot above are: x=1, y=10 and x=2, y=0 .

This is a screenshot of my UIViewController ( GraphingViewController ) I have a separate view nested within here that is the host view for the graph. My code for the graph is exactly the same as SimpleScatterPlot.m with the exception of the generate data method which I have customized:

-(void)generateData
{
    NSMutableArray *contentArray = [NSMutableArray array];
    int counter = 0;
    for (NSNumber * entryValue in self.plotDataArray) {
        counter++;
        id x = [NSDecimalNumber numberWithInt:counter];
        id y = [NSDecimalNumber numberWithInt:[entryValue intValue]];
        [contentArray addObject:[NSMutableDictionary dictionaryWithObjectsAndKeys:x, @"x", y, @"y", nil]];
        NSLog(@"setting values for graph x: %@ and y: %@",x,y);
    }
    plotData = [contentArray retain];
}

Another thing that is strange is that I can scroll left and right but not up or down. I have in prior changes had the x,y start at 0,0 but that hides the x axis, so although its what I want, I cant have that line hidden.

How can I start the graph at 0,0 and be able to scale it to not only see all points but also to see the labels (" X Axis ", " Y Axis ")? Also the Y axis is going by .2 and X by .5 as you can see. These should be 1 as all of my numbers would be whole numbers.

Answer 1

The way I implemented it is the same way. I keep track of the min and max X and Y values from the data, and then set the plot range accordingly.

// Adjust the plot space according to the min and max x/y values
plotSpace.xRange = [[CPTPlotRange alloc] initWithLocation:CPTDecimalFromInt([self.minTime intValue]) length:CPTDecimalFromInt ([self.maxTime intValue] - [self.minTime intValue])];
plotSpace.yRange = [[CPTPlotRange alloc] initWithLocation:CPTDecimalFromInt([self.minScore intValue]) length:CPTDecimalFromInt (([self.maxScore intValue] - [self.minScore intValue]))];

Answer 2

The easy way to keep the axis labels visible is to not set the titleLocation . The default value of NAN will position the label in the center of the plot area.

The globalYRange is preventing vertical scrolling. The default value of nil does not limit scrolling. If you do want limit scrolling, but need to change the plot range to show new data, set the global range to nil , update the plot range, and reset the global range.

The tick locations and axis labels are controlled by the axis labeling policy. The default fixed interval policy will work, just leave the majorIntervalLength at the default value of one (1).

Answer 3

你尝试过scaleToFitPlots方法吗？

 [plotSpace scaleToFitPlots:[NSArray arrayWithObjects:scatterPlot, nil]];

Answer 4

I fixed one part of the problem which was that the high points where not being shown. This line of code was limiting the max Y Axis

CPTPlotRange *globalYRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromFloat(0.0f)
                                                          length:CPTDecimalFromFloat(2.0f)];

So I created a property to keep track of the largest value and set this to that:

CPTPlotRange *globalYRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromFloat(0.0f)
                                                          length:CPTDecimalFromFloat(self.largestYvalue)];

So now I have this:

I still need to figure out how to get X Axis label to show (Ill update If I figure it out or still accepting answers for that).