Margin for scatter series in Shinobi Charts on iOS - ios

I'm using a scatter series in Shinobi Charts but points with maximum and minimum x and y values are being truncated because they're at the edge of the plot area?
How can I add a small margin to the plot area so I can clearly see the scatter points and none are truncated. I realise that I can set the range of each axis myself but that gets into nasty math to work out what a 5px margin would be over the lowest/highest values etc.

There are 2 properties on SChartAxis which can help you: rangePaddingLow and rangePaddingHigh. These values are absolute values, and in the scale of the axis.
For example, if you have an axis which has an automatic range of (0,100), then the following would update the range to (-5, 105):
axis.rangePaddingLow = #5;
axis.rangePaddingHight = #5;
As the axis scale updates, these padding values will be maintained.

Related

my vertical x axis labels run into my plotted data. Is there a way to compress the graph so I have a little extra room at the bottom

I am plotting my x axis labels vertically, and using the following line to provide a little space under the axis
axisSet.xAxis.axisConstraints = [CPTConstraints constraintWithLowerOffset:40.0];
But now the vertical length of the label bumps into the first value on the y axis. Is there a way to compress the graph a little so the first value on the y axis begins a little higher? Thanks.
Adjust the axis' labelAlignment and/or labelOffset to reposition the labels.

Proportional Pie-charts using High-Charts

I am working with High Charts to plot two pi charts which I need to be proportional. I have calculated the radius of each, but can't find a way to specify a radius for each pi chart. How can I do this?
Use pie series size property.
From docs:
size: String|Number
The diameter of the pie relative to the plot area. Can be a percentage or pixel value. Pixel values are given as integers. The default behaviour (as of 3.0) is to scale to the plot area and give room for data labels within the plot area. As a consequence, the size of the pie may vary when points are updated and data labels more around. In that case it is best to set a fixed value, for example "75%". Defaults to .
example

ios Core plot - scatter plot circles overlap with x, y axes

I am currently plotting certain data using Scatter Plot of Core Plot. The size of the circles depends on the frequency of occurrence of the particular value. On plotting, I find that some of the circles are overlapping and crossing the x and y axes.
Is there any method to check if a circle (i.e, plot point) crosses the axes and automatically resize the circle so that it does not cross the axes?
Edit - The axes are fixed. So I cannot change the axes.
Edit - I would like to know which methods to use to determine if a circle crosses/touches the x or y axis. Currently the circle overlaps if the size of circle is 12 and its y coordinate is 1.1. I am unable to understand how the size is being mapped to the circle on the plot. Thanks.
No. The easiest way around this problem is to figure out how big the largest circle will be and adjust the plot ranges on the the plot space to leave at least that much space between the extreme data points (smallest and largest) and the axes or other edges of the plot space. The plot space has methods to convert back and forth between data coordinates and pixels in the coordinate space of the plot area layer.
The point conversion methods are:
(data to plot area)
-(CGPoint)plotAreaViewPointForPlotPoint:(NSDecimal *)plotPoint
numberOfCoordinates:(NSUInteger)count;
-(CGPoint)plotAreaViewPointForDoublePrecisionPlotPoint:(double *)plotPoint
numberOfCoordinates:(NSUInteger)count;
(plot area to data)
-(void)plotPoint:(NSDecimal *)plotPoint numberOfCoordinates:(NSUInteger)count
forPlotAreaViewPoint:(CGPoint)point;
-(void)doublePrecisionPlotPoint:(double *)plotPoint
numberOfCoordinates:(NSUInteger)count
forPlotAreaViewPoint:(CGPoint)point;
Depending on your application, you might be able to expand the plot range by a simple factor using -expandRangeByFactor:. You can find the factor for the xRange by dividing the width of the plot area plus the circle diameter by the width of the plot area. Do a similar calculation for the yRange using the height of the plot area.
Perhaps you could check to see if half of the diameter is greater than both the x and y value of the plot. If it is greater, then reduce the diameter to equal twice the smaller of x and y.

CorePlot YAxis with two types of Scaling

Is it possible to achieve different scaling for positive part of Y-axis and different scaling for its negative part of Y-axis.The idea is to show most part of plot area for positive values and less part for negative values.
Set the yRange of the plot space so that 20% of the range is negative. For example, a range with a location of -25 and length of 125 meets this requirement.

Core Plot - X-Axis moving position when plotting less points

I have a strange problem where my x-axis moves down the plot area when I'm plotting less points. My graph has 2 lines plotted - 1 for previous year and 1 for current year values. My original graph always plotted 12 points for both lines, regardless of which month we are in and this works fine. I have now changed my app so that the current year line only plots points upto the current month. E.g. we are in May so I only plot 5 points. When I do this the x-axis moves down the plot area so that it is detached from the y-axis and the labels are hidden - see screenshots :
Why would simply reducing the number of plot points change the x-axis position? I'm using Core Plot 1.1 (static library) and Xcode 4.6.2.
The yRange of the plot space changed so the point where the x-axis crosses the y-axis is now too close to the bottom edge of the graph. You have two options:
Ensure the yRange always puts the crossing point (the "orthogonal coordinate") far enough from the edge that the labels and title remain visible.
Use the axisConstraints to position the axis a fixed distance from the edge of the graph. This will let the crossing point float along the y-axis.
The plotting library changes the x-axis position because generally core plot take the minimum and maximum range among the values of y axis. You when you provide only 5 points then the lowest value is taken from y axis values and there for x- axis position while when you were providing all 12 months values the lowest value of the rest of the month were 0 and therefore x-axis was at zero. You can change the maximum and minimum values for the y range in core plot.

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