# XYChart « Chart « JFreeChart Q&A

### 1. JFreeChart XY-chart that refreshes with new set of data? Example?    stackoverflow.com

I want to learn how to learn how to create some charts with jfreechart and googlefor some examples. but I couldn't find what I need. This here is good

### 2. Smoothing function, or best-fit line for XY Chart    jfree.org

Maybe it'd be possible to do this by imagining 3 coordinates for an easy example: taking 1st and 2nd points and figuring out their slope from the x,y coordinates. Do the same and find the slope for points 2 and 3. Then taking the two slopes average them together and you have the best fit line possibly? And then once you ...

### 4. XY Chart with equidistant ticks    jfree.org

Hi there, I am trying to get an XY Graph. Now I want to have the distance between ticks on the X-axis and the Y-axis having the same amount of space. So say the X has 0 to 8 and the Y 0 to 5. I am using ServletUtilities to render this into png but since I need to give an ...

### 5. XY chart with shapes at points only when sufficiently zoomed    jfree.org

I am wondering what is the cleanest (read easiest) way to only make shapes on an XY plot visible when the plot is zoomed in past a certain level (i.e. if the range of values currently visible on e.g. the range axis is below a certain threshold, then enable the shapes). The problem is I have a dense graph with tens ...

### 6. method for limiting the number of symbols on an XY chart?    jfree.org

my xyPlots have many points, and assigning shapes to some of the points would be helpful in identifying each line on a plot. With a shape at each point, it is hard to differentiate each line. With that being said, is there a method out there for limiting the number of shapes on an XY Plot. I do have the documentation, ...

### 7. Change lables using XY chart    jfree.org

Hi all, I am trying to create a XY line chart. I have succeeded, but the labels on the range axis are the numbers that I have added to the dataset. I want the chart to be build using the numbers, but the labels should not be these numbers, they should be Strings. Is that possible? How should I do this? ...

### 9. Shapes in XY Chart    jfree.org

Hi, I can't get the sjape to show up in my charts. I'm using 1.0.1 on WinXP I have tried: myShape = new Rectangle(2,2); renderer.setSeriesShape(i,myShape); renderer.setBaseShape(myShape); What I want is a circle (or any shape) in each "dot" to show that values might be missing between dots. I don't want to put null for those values to "break" the line. In ...

### 10. What's the best method to add a dynamic cursor on an XYchart    jfree.org

I would like to add a dynamic vertical cursor to the chart and then be able to refer to the exact current Y values dynamically. while moving on the chart. my series are based on a discrete int X axis (within the XYdataset). I tried to add a new series, but if the cursor is positioned at X=n, this systematically erases ...

### 12. Problem plotting XY chart with 3234 datapoints    jfree.org

Hi I am trying to make a XY plot whith 3234 datapoint and I get no result, I get only the square with a red X in upper left corner. Indicating that no image was found. I am using the following Container Tomcat 5.5.15, OP system Window2003 Server CeWolf-1.0 (JfreeChart 1.0.0) There is no error in thr log files and the ...

### 13. XYChart Crosshair click bug?    jfree.org

I'm using an XYChart with use of the crosshair functionality which matches closely to CrosshairDemo4.java. This example states that the crosshairs will lock on the nearest data point. The Crosshairs visibly migrate to a valid point, but the double x = plot.getDomainCrosshairValue(); double y = plot.getRangeCrosshairValue(); don't update unless you double-click. Is there a reason for this? I am capturing this ...

### 14. exception IncompatibleClassChangeError in XY chart    jfree.org

Hi , I have created a XY chart using the Jfree chart lib when I run it is eclipse it runfine with no error and graph has created but when I place the same code in JSP (I am using tomcat 5.5) it gives following error. any idea .. javax.servlet.ServletException org.apache.jasper.runtime.PageContextImpl.doHandlePageException(PageContextImpl.java:848) org.apache.jasper.runtime.PageContextImpl.handlePageException(PageContextImpl.java:781) org.apache.jsp.XYChart_jsp._jspService(org.apache.jsp.XYChart_jsp:87) org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:97) javax.servlet.http.HttpServlet.service(HttpServlet.java:802) org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:322) org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314) org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264) javax.servlet.http.HttpServlet.service(HttpServlet.java:802) root cause ...

### 15. Need XY-Chart filled with arrays    jfree.org

Hi Folks, as I'm completely new in JFreeChart and i do need it for a project at School (reading from a microchip device and using NetBeans) i would like to ask for your kind help. Recieving the values from the device and reading it in, i need to create a chart with x and y values (where x is a time ...

### 18. Advice: How to get items from XYChart by specifying XY vals    jfree.org

Advice: How to get items from XYChart by specifying XY vals by nabinabi Mon Jun 04, 2007 4:04 pm Hi, For everyone who has looked for a method to get an XYItemEntity from a simple XYChart by by specifying the x and y value (axis values). Code: Select all private XYItemEntity getChartItem(int x, int y){ ...

### 19. XY chart questions    jfree.org

Hi; BTW - it looks like JFreeChart can do just about everything Excel can do for XY charts. A couple of questions: 1) Is there a way in polar charts to set the range of the circle or is it always 360? 2) For scatter charts is there a way to have it fit a smooth line to the points? 3) ...

### 21. Problem with XY chart    jfree.org

Hi All, I'm using Time as my Y-axis.(Eg:-14:00,15:00) The problem is the same "time" is repeated so many times in the y-axis. Like 10:00 is seen twice... Can any one of you help me to resolve this problem. x-axis is Date -its working as desired. Thanks in Advance. Any one of you aware why we will get the following exception stack ...

### 22. Labels or numbers for points at XYchart.    jfree.org

Labels or numbers for points at XYchart. by creat89 Wed Nov 21, 2007 5:43 am Hi. Well, i need to get a laber (number) for each point that it is created, here is the code: Code: Select all XYSeries objDatos = new XYSeries("Aproximacin por iteracin"); while (error>=tol) { ...

### 23. I want to know Y coordinate by X value of XYChart    jfree.org

Sorry my bad enlgish, I want to know a y coordinate of a plotted XYChart by the x coordinate. For example. I have a cosine wave form when I put im my jtextfield the coordinate x: for example x = 0; the program returns to me a y coordinate. In this example I put x=0 , and the software returns to ...

### 25. Get value of a point on xy chart    jfree.org

The source to the demo is part of the \$50 documentation package that the author sells separately. I can't send it to you, but perhaps when David sees this he will have other options. Alternatively, if one of the other users who sees this has working code in this topic area, they will send you an excerpt from their own code. ...

### 26. Splitting the XYPlot background in an XY Chart    jfree.org

Hi, I am working with TimeSeries charts and had a question about rendering the background in the XYPlot class. I want to split the plotting background such that the area above a given Y-axis value is painted Red and the area below is painted Green. What would be the best approach for this? Cheers, -K

### 28. How to only show some points in XYChart    jfree.org

Hi , I wanna know how to show some points in one line , there is a line with lots of points , but I wanna some points to show only, e.g. in a month , just show ten days'value,the other days not to , I used renderer.setPlotShapes(false); all the points disapeared, but how to just show some point? any help ...

### 29. Draw line at offset on XY Chart    jfree.org

Hi There, I'm able to draw a straight line through the Chart. However I need to draw this line at some displacement from Y-axis. This is a line start with hight Y-axis values and end with 0.0 X-axis value as your go from left to right. The first X-Y point needs to start at a specified displacement from Y-axis. I'm using ...

### 31. How make color specific coordinate value of XY chart    jfree.org

Hi, I have already created a xy-chart using jfreechart.But i have to do color in a specific coordinate value of XY chart. Suppose when my x-axis value is 5 i have to do red color in chart at that point. I can't able to do it. I am using this code ValueAxis timeAxis = new DateAxis(""); timeAxis.setVerticalTickLabels(true); NumberAxis valueAxis = new ...

### 32. Shadow in XY Chart    jfree.org

I just upgraded from 1.0.10 to 1.0.13. I have a chart using IntervalXYDataset that is very similar to XYSeriesDemo3. Using 1.0.10, there are no shadows on the bars, however with 1.0.13 there are shadows. How do I remove the shadows? I don't see any method to remove the shadows. The BarRenderer has a setShadowVisible() method, but I don't see a similar ...

### 33. Problem with simple XYchart    jfree.org

package de.vogella.jfreechart.swing.pie; import javax.swing.JFrame; import org.jfree.chart.ChartFactory; import org.jfree.chart.ChartPanel; import org.jfree.chart.JFreeChart; import org.jfree.data.xy.XYDataset; import org.jfree.data.xy.XYSeries; import org.jfree.data.xy.XYSeriesCollection; public class XYchart extends JFrame { private static final long serialVersionUID = 5356206087416253419L; public XYchart(String applicationTitle, String chartTitle){ super(applicationTitle); XYSeries series = new XYSeries("Average Size"); series.add(20.0, 10.0); series.add(40.0, 20.0); series.add(70.0, 50.0); XYDataset xyDataset = new XYSeriesCollection(series); JFreeChart chart = ChartFactory.createXYAreaChart( chartTitle, "Height", "Weight", xyDataset, null, ...

### 36. JFreeChart: Getting items from XY-Charts by specifying XY-Coordinates    forums.oracle.com

Ok, but this is not exactly what i wanted. here is some detailed explanation: The user can choose some of the items displayed on the chart by making a right click and than dragging the mouse to some other point. When dooing this a rect is drawn, so the user sees what will be selected. So what I want is to ...