I am using core plot to make a line graph for my iPhone app. So far I successfully made the line graph from my xml data.
Furthermore I added a text layer that shows the value (for example 40) once I select the cell
holding the value 40. For this, I use the function:
(CPTLayer *)dataLabelForPlot:(CPTPlot *)plot recordIndex:(NSUInteger)index
So now I want to have a vertical line on the graph to indicate the selected value (the 40). I tried adding CPTBarplot but somehow the bars show only at the beginning of the graph axis.
Is there a function from core plot like the above that will create a line indicator?
I would appreciate if someone can give me some hint how to solve this problem and thank you very much in advance.
You could use a scatter plot for that. There's a point selection demo in the Mac CPTTestApp that draws a crosshair over the selected point. It would be trivial to modify that to only draw the vertical line.
The -numberOfRecordsForPlot: datasource method returns the number of points in the selection indicator (5 for the crosshairs) or zero (0) if there is no current selection. The -numberForPlot:field:recordIndex: method returns the points in the indicator. The points are drawn in this order:
Left
Right
Center (with plot symbol)
Top
Bottom
The -symbolForScatterPlot:recordIndex: method controls the plot symbol in the center. You can eliminate this method if you don't need any symbols on the indicator plot.
Related
I have a visualization (below) that is a combination Stack bar and Line graph . I am trying to format the data labels for the line graph totals- so that they all hover above the stacked bar. This works(with default settings) for all of the dates except the first bar (see image below- highlighted in yellow). There appears to be no formatting options available for the data labels of the line graph to control the label position (unlike in the stacked bar).
Any suggestions on how to force the totals to always appear above the bars?
A simple example file is available here https://drive.google.com/file/d/1m4qicc5gv5fCmVPiBe2m6THuHGKjacnx/view?usp=sharing
Any suggestions appreciated.
Go to Format > Y-Axis > Show secondary and set it to the Off position and it should look like this:
What's happening is that your line and bars were on independent axes, which makes them align not how you intend.
PowerBI supports Total labels for stacked visuals:
You can now turn on total labels for your stacked bar/column, stacked area, and line and stacked column charts, allowing you to see the aggregates of your data at a glance
In a context of a line chart displaying time data in regular intervals where multiple series might overlap what would be the optimal way to:
A) hint the user that the chart has overlapping series?
B) give the user the capability to visualize all those series? Like spanning the series somehow?
For overlapping series in a line chart, I would keep the traditional line chart but put a label at the end of the graph with a color legend. The legend and label will help the user get information quickly.
Another version of a line chart for overlapping series can be a line area chat.
If you are not stuck on only line charts, I would suggest a bar chart. Below are some examples that you can use.
Example 1:
Example 2:
Example 3:
There are couple ways to indicate that there are overlapping series on a chart. You can increase the marker radius of one of them. The number of legend elements tells you how many series there is, too. Finally, you can distribute series on a different yAxis, with different top and height properties. Also, in styled mode, when you hover on legend item, other series opacity changes.
API Reference:
http://api.highcharts.com/highcharts/plotOptions.line.marker.radius
Examples:
http://jsfiddle.net/whsgpdyw/ - changing marker radius
http://jsfiddle.net/fuq6j4sg/ - each series on a different yAxis
I'm trying to create a stacked graph using core plot.i have followed this tutorial.I have a UISlider on sliding i'm updating my graph.The issue i'm facing is my top value for y-axis is touching top border(As in the screen shot). As per my requirement in need to round off the highest value to next 10th value so that my graph doesn't touch the borders.On changing my slider value the x and y axis should also get refresh,i'm doing it by regenerating plot but it takes a lot of memory.Any idea how can i achieve these requirement ?
Don't recreate the whole graph every time the values change. Call -reloadData on the graph to refresh the plot data and set the xRange and yRange of the plot space to change the scale of the axes.
I'm trying to get and set the position of a draggable legend in matplotlib. My application consists of an interactive GUI, which has a redraw/plot function that should perform the follow steps:
save the position of the current legend.
clear the current axes and perform various plotting operations, which may or may add labels to their plots.
build a new draggable legend (ax.legend().draggable()) and restore the old position of the legend.
In between these steps the user is free to drag the legend around, and the goal is to persist the legend position when the plots are redrawn.
My first approach was to use oldpos = legend.get_bbox_to_anchor() and legend.set_bbox_to_anchor(oldpos) in steps 1 and 3. However this causes to move the legend completely off the visible area.
Note that I have to use ax.legend() and cannot use fig.legend(lines, labels), since step 2 is completely decoupled, i.e., I don't know anything about lines and labels in step 3. According to answers to the question How to position and align a matplotlib figure legend? there seems to be a difference between these two possibilities regarding axes or figure coordinates. Obviously my problem calls for figure coordinates, but I haven't fully understood how to convert the bbox to a "bbox in figure coordinates".
The even more severe problem I just realized is that apparently legend.get_bbox_to_anchor() always seems to return the same values irrespective of the drag position. So maybe the anchor can only be (ab-)used to manipulate the position of static legends? Is there another/proper way to save and restore the position of a draggable legend?
By looking at the implementation of Legend I found out that there is an undocumented property _loc, which exactly does what I want. My solution now looks astonishingly simple:
oldLegPos = ax.get_legend()._loc
# perform all plotting operations...
legend = ax.legend().draggable()
legend._loc = oldLegPos
It looks like _loc automatically stores figure coordinates, since I do not have to convert the coordinates in any way (eg. when the plotting operations completely change the axes ranges/coordinates).
I'm trying to make a simple app where a chart is drawn with a line and X axis. I want to fill parts of the view enclosed by chart and X axis with gradient. To fill them I use the following code
CGContextSaveGState(c);
CGContextAddPath(c, CGContextCopyPath(c));
CGContextClip(c);
CGContextDrawLinearGradient(c, g, previousPointOfIntersection, intersectionPoint, 0);
CGContextRestoreGState(c);
every time the line crosses the X axis. However, the problem is that the gradient fills the whole view between previous point of intersection and current one.
Is this a right way to draw a gradient for a part of view enclosed by lines?
I'd be very happy to hear any suggestions regarding my problem :)
P.S. here's the code of my class http://pastebin.com/wYiHkuVi
I'd say you don't have the path in the context that you think you do.
If you've "stroked" the path for your graph it's been used up.
Replace your Add Path with:
CGContextAddEllipseInRect(c, self.bounds);
to see if you get some clipping occurring.
If so, then you need to rebuild your path here instead of the AddPath/Ellipse code.