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Closed 10 years ago.
On a recent Java project, we needed a free Java based real-time data plotting utility. After much searching, we found this tool called the Scientific Graphics Toolkit or SGT from NOAA. It seemed pretty robust, but we found out that it wasn't terribly configurable. Or at least not configurable enough to meet our needs. We ended up digging very deeply into the Java code and reverse engineering the code and changing it all around to make the plot tool look and act the way we wanted it to look and act. Of course, this killed any chance for future upgrades from NOAA.
So what free or cheap Java based data plotting tools or libraries do you use?
Followup: Thanks for the JFreeChart suggestions. I checked out their website and it looks like a very nice data charting and plotting utility. I should have made it clear in my original question that I was looking specifically to plot real-time data. I corrected my question above to make that point clear. It appears that JFreeChart support for live data is marginal at best, though. Any other suggestions out there?
I've had success using JFreeChart on multiple projects. It is very configurable. JFreeChart is open source, but they charge for the developer guide. If you're doing something simple, the sample code is probably good enough. Otherwise, $50 for the developer guide is a pretty good bargain.
With respect to "real-time" data, I've also used JFreeChart for these sorts of applications. Unfortunately, I had to create some custom data models with appropriate synchronization mechanisms to avoid race conditions. However, it wasn't terribly difficult and JFreeChart would still be my first choice. However, as the FAQ suggests, JFreeChart might not give you the best performance if that is a big concern.
I just ran into a similar issue (displaying fast-updating data for engineering purposes), and I'm using JChart2D. It's pretty minimalist and has a few quirks but it seems fairly fast: I'm running a benchmark speed test where it's adding 2331 points per second (333x7 traces) to a strip chart and uses 1% of the CPU on my 3GHz Pentium 4.
Live Graph supports real-time rendering.
I'm using GRAL for real-time plotting. It's an LGPL Java library. Although it's not as powerful as JFreeChart it has a nicer API. I got a plot up and running in very short time. They also ship a real-time plotting example.
I found this question when I was googling for open source plotting libraries for java. I wasn't quite happy with the answers posted here so I did some further research on the issue.
Although this question has been posted back in 2008 this might still be interesting to someone.
Here is a list of Open Source Charting & Reporting Tools in Java
http://autoplot.org/ allows for real-time updates and can be used to create many types of scientific plots.
To update the plot, specify the URL to a data file and then append &filePollUpdates=1&tail=100. See the example at http://autoplot.org/cookbook#Loading_Data
Waterloo Scientific Graphics is a new LGPL project. Data objects are observable and could be updated in a real time plotting scenario.
For details see http://waterloo.sourceforge.net/
A few screenshots:
The library I wrote, Plot4j, also supports real-time plotting.
I used JFreeChart (http://www.jfree.org/jfreechart/) on a previous project. It has some very good built-in capabilities, and the design was WAY extensible so you could always roll your own extension later if you needed some custom chart annotation or wanted an axis to render differently, or whatever. It's definitely worth checking out.
Check ILOG's JViews - they have a lot of stuff and something might fit your needs. All of them are extremely configurable and quite fast. Not free though.
I've used JFreeChart in a rather complex application that needed to visualize data streams and calculations based on the data. We implemented the ability to visually edit the data plots by mouse and had a very large set of data points. JFreeChart handled it very well.
Unfortunately I was stuck with v0.7, but the newest release are sooo much better when it comes to API clarity. The community is very helpful and the developers are responding to mails too.
If you're doing a web application and don't want to bother with libraries, you can check the Google Chart API. Didn't use it myself, but I started some tests which were very promising.
For real-time plotting you can use QN Plot, JOpenChart or its fork Openchart2.
JHandles is an alternative graphics package for Octave (a math package). It is probably worth looking into, but being Octave specific may not have what you need.
-Adam
PtPlot
may be a good choice. Formerly called Ptolemy.
jcckit can handle real-time plotting. It's a bear to use though.
I forked it, and made a very simple wrapper around it for non-realtime plotting. The underlying complicated interface can be used directly too.
https://bitbucket.org/hughperkins/easyjcckit
You might want to check out JMathPlot
Related
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Closed 9 years ago.
I'm a developer familiar with Ada, C, Obj.C (iOS), and C#. I would like to create an application to show some data about a robot I'm building. However I have never done graphics with either Mac libraries or OpenGL before.
What I'm trying to achieve is shown in the image below. I have tested Processing to create some stuff. But it's too complicated and Processing is far from powerful for this kind of application. It can't even rotate a line around its center without writing some nasty code.
Requirements:
Graphing capabilities (e.g. voltage drawn in respect to time), Google maps API, gradients, 2D animations, masks.
Questions:
What should I learn? Is this possible to implement using only the Mac libraries/frameworks or should I use OpenGL?
Is it best to do it using Obj c? Or is java worth the learning? How good is Java with graphics like this? This thing is that if I program this using Obj C then its not cross platform.
Any other tips you can give?
Later on, I´d like to add a google maps to show the position of the plane. All data is transmitted through Wifi. 10Hz.
Here is a thread of someone doing this with opengl and js: http://www.jpct.net/forum2/index.php?topic=3076.0
Yes you can do this in opengl, but you may consider Cairo which is 2d rendering and may be simpler. It certainly depends on if you need 3d rendering or not. In case of 3d rendering OpenGL may be a better bet, then trying to fit it into the Cairo system.
If you want it to be cross platform, I'd personally do it in Java or Python, but there are opengl and cairo bindings for most languages. If java I recommend trying LWJGL.
You'll also need to consider what UI framework to use, since you may need buttons and all that jazz. I personally like Qt, but WPF is also quite good.
See here for Cairo Docs: http://cairographics.org/documentation/
In addition this question came up here and there are more suggestions in the comment threads: http://www.gamedev.net/topic/479476-how-would-you-program-a-pfd-primary-flight-display/
I'm not sure how great animation with cairo is, but here is a tutorial demonstrating that: http://cairographics.org/threaded_animation_with_cairo/
I dont think that some specific library will accomplish all the requirements. Probably you will need to use a mix of them.
If you ask me, Id go for a combination of web ui frameworks. Based on the image you have shared, im sure that most of that graphical components can be constructed using ExtJs framework (see these examples: http://www.sencha.com/products/extjs/examples/, http://docs.sencha.com/ext-js/4-2/extjs-build/examples/charts/Gauge.html, http://docs.sencha.com/ext-js/4-2/extjs-build/examples/sandbox/sandbox.html).
For the central panel, maybe there is no library that provides a generic widget like that, and so I would go for a custom HTML5 Canvas implementation (http://en.wikipedia.org/wiki/Canvas_element).
Just want to add that I woudl go for the web way simply because:
Community is BIG for almost any library
Cross platform issues would not be a problem
Most of Web UI frameworks are mature, and have out of the box widgets ready to be used.
Communicating with external APIs (like Google Maps as you mentioned) is a piece of cake using web.
Ah, this is personal experience I've had while I built my final year engineering project(which was incidentally a robot that could fly) - And I've built something like this before.
I used Java for graphing and telemetry data tool with flight display system like that(and it was sufficient).
But if you are good with a programming language, then you can do it in any language of your choice. Yes, Mac + OpenGL + ObjC is good combination too. My aim was to keep the code as portable as possible.
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Closed 10 years ago.
I'm Developing a CBIR (Content based Image Retrieval System) as part of my BE project.
Which of the below mentioned tools will be better to be used for image processing??
1-> Matlab
2-> Mathematica
I'm planning to develop this system using java as a front end of the system. which of above systems will be better. Or should I go for some 3rd party image processing API's available for java ????
I used Mathematica for years and still found it easier to learn Matlab from scratch in order to do an image processing project. The thing that makes Matlab better here is that many state-of-the-art image algorithms have code available. For instance, for content-based image retrieval you need to extract content features, and vl_sift library does that. Also, you can bundle your Matlab library to run as a stand-alone executable, and I don't know if that's possible with Mathematica.
I previously suggested ImageJ and others mentioned ImageMagick since I mentioned Java environment. However, I would like to change my suggestion. I came across Intel's OpenCV (Opensource Computer Vision) libraries. This is a great set of libraries for use with C, C++ and Python. This is cross platform too! So porting the code shouldn't be too difficult.
Why I think OpenCV is great is because even novices (like me) in Image Processing can use it. for example, smoothing an image is as easy as calling one function cvSmooth() with a few parameters on which type of smoothing (blur, gaussian etc). It supports much more advanced functions such as Optical flow and blob tracking. And the great thing is, its quick to test out or build simple image transforms.
for more info please go to http://opencv.willowgarage.com/wiki/ . Here you'll find cheatsheats, reference manuals, examples and some tips. great help and starting point.
Thanks
What are your criteria for measuring the relative superiority of programs for image processing ? For example, if you are a Mathematica expert then you will find it easier to use Mathematica for the task. On the other hand, if you are a penniless student then you will find Java and some of its libraries more to your taste.
EDIT: in answer to OP's comments ...
'ease of image processing' is entirely subjective -- if you don't know Mathematica then it will be difficult to use it for image processing -- so this one is your call.
'processing time' is entirely objective -- but do you have the time to try out all 3 of your suggested options and compare them ? For a BE project you'll be far better using the tool you are most comfortable with and spending as little time as you can wrestling with an unfamiliar tool for the sake of a bit of extra speed.
'cellular automata' for image processing -- don't know how relevant it is, but Mathematica has inbuilt functionality for cellular automata.
I would look into the ImageMagick/GraphicsMagick family (SO discussion), which has several Java wrappers (e.g., JMagick).
you could use ImageMagick or why not look into the JMF (Java Media Framework)
Matlab is the better of the two. It has huge built in libraries and implementations of thousands of algorithms. Its fast, easy and well documented.
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Closed 11 years ago.
I want to know what is the best open source Java based framework for Text Mining, to use botg Machine Learning and dictionary Methods.
I'm using Mallet but there are not that much documentation and I do not know if it will fit all my requirements.
I honestly think that the several answers presented here are very good. However, to fulfill my requirements I have chosen to use Apache UIMA with ClearTK. It supports several ML Methods and I do not have any licences problem. Plus, I can make wrappers to other ML methodologies, and I take the advantage of the UIMA framework, which is very well organized and fast.
Thank you all for your interesting answers.
Best Regards,
ukrania
Although not a specialized text mining framework, Weka has a number of classifiers usually employed in text mining tasks such as: SVM, kNN, multinomial NaiveBayes, among others.
It also has a few filters to wok with textual data like the StringToWordVector filter which can perform TF/IDF transformation.
Check out the Weka wiki website for more information.
Maybe have a look at Java Open Source NLP and Text Mining tools.
I've used LingPipe -- a suite of Java libraries for the linguistic analysis of human language -- for text mining (and other related) tasks.
It is a very well documented software package, and the site contains several tutorials which thoroughly explain how to do a certain task with LingPipe, such as named entity recognition. There is also a newsgroup, wherein you can post any question you have about the software (or NLP related tasks), and have a prompt reply from the authors of the package themselves; and of course, a blog.
The source code is also very easy to follow and well documented which, for me, is always a big plus.
As for Machine Learning algorithms, there are plenty, from Naïve Bayes to Conditional Random Field. On the other hand, for dictionary-matching algorithms, they have an ExactDicitonaryChunker, which is an implementation of the Aho-Corasich algorithm (a very, very, fast algorithm for this task).
In sum, I think it is one of the best NLP software package for Java (I haven't used every single package that is out there, so I can't say it's the best), and I definitely recommend it for the task that you have at hand.
You may already know about GATE: http://gate.ac.uk/
...but that's what we've used (at my day job) for lots of different text mining problems. It's pretty flexible and open.
I built a maximum entropy named entity recognizer for CoNLL data using OpenNLP MaxEnt http://sourceforge.net/projects/maxent/ for a course once.
Required a lot of data preprocessing with custom perl scripts do get all the features extracted into nice neat numerical vectors though.
We use lucene to process live streams from the internet. It has a native java api.
http://lucene.apache.org/java/docs/
You can then use mahout which is a bunch of machien learning algorithms which operate on top of lucene.
http://lucene.apache.org/mahout/
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Closed 11 years ago.
When I use Java applets, they tend to be slow, don't integrate very well with the browser environment and often require a few click throughs ("No, I don't want to give this unsigned application free reign of my hard disk").
So, I'm curious.
Are these problems insurmountable? Are there Java applets out there which integrate well with the browser experience (in, for example, the way a well-designed Flash application does?) Can you point out any examples of really "nice" Java applets?
I'm asking this because I want to know if I should be taking a more serious look at Java-in-the-browser, or if Flash will remain dominant for the foreseeable future.
Edit: Unintentional flame bait has been removed. Sorry for any offence caused.
The Facebook asynchronous image uploader is a Java applet.
Update: Apparently not developed in house at Facebook. This seems to be the product.
Amendment:
Now that the question has been updated to be a bit more concise, I thought I'd add more to this answer.
This kind of problem, a mass image uploader (in this case), is the kind perfectly solved by a Java applet. Why?
It uses native UI elements, so users are not confused, or have to learn a new interface.
It can save massive amounts of bandwidth and overhead, because image transformations, such as resizing and cropping, can take place on the client side, rather than the server.
Write once, deploy everywhere (almost, sorta).
Visual Thesaurus is the coolest / best applet I know of.
Check out PulpCore. A really awesome Java applet framework:
http://www.interactivepulp.com/
Performance for it seems pretty amazing too if you check it out on bubblemark.com
Some of Ken Perlin's applets are beautiful.
see http://mrl.nyu.edu/~perlin/
eg:
http://mrl.nyu.edu/~perlin/experiments/unicycle/
http://mrl.nyu.edu/~perlin/homepage2006/simplex_noise/index.html
http://mrl.nyu.edu/~perlin/experiments/orange/
(...)
Simple floor plan designing with java applet here. Works much faster than dragonfly.autodesk.com or floorplanner.com (both are flash applications).
A few things...
Some game sites, like popcap.com, use Java applets for their games, and they look pretty good and are very usable.
As far as "why is that button cropped?" - that's probably a layout manager issue. See my article on layout managers, in particular:
http://java.sun.com/developer/onlineTraining/GUI/AWTLayoutMgr/shortcourse.html#whyNeed
There are many nice looking applets created with Processing (which is basically Java with some fancy graphics libraries included).
Just take a look at this visualization.
(source: zumkuckuck.com)
In high school I used to play a ton of Yahoo Games and I'm pretty sure those are all java applets. It looks like Yahoo have updated their site since I went there last but you can still find all of the old games here.
The MMORPG Runescape uses a Java applet as a client, and works very nicely, although the graphics aren't nearly as good as other games of the type I've seen. Jagex, the publishers, also have a game site called Funorb.
Another game which is in Java (though not an applet) is Puzzle Pirates. It's not exactly beautiful but it's cute and it's very addictive. Also, it's very speedy and smooth (which has been a knock against Java applets).
Java applets are like flash scripts - They can be used for good, but are often used for evil (e.g., annoying banners). IMHO the main reason that they didn't catch on is that they require tended to require too much skill and used AWT/Swing which produces worse UIs than what a designer with little programming skills could achieve with flash.
I would say that yes, they still exist, but more for business goals that don't require pretty UIs. For example, A lot of web-based statistics calculation tools are based on nice applets.
It's certainly possible. Java2D (the standard graphics component in Java) is capable of rendering beautiful stuff. A big problem is that the default Swing Look and Feel is ugly. I believe Java 7 will have a better one, but there are also very beautiful third party ones such as Substance. I've personally developed a small Java applet game which, apart from the jagged text in the intro screen (which is a bitmap, not rendered text) is visually indistinguishable from a Flash game.
My mom is addicted to the casual gaming at pogo.com, and I've gotta say, they've done an amazing job at fun, easy to learn, nontraditional games that look perfect. I'd love to see their code, honestly.
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Closed 9 years ago.
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There was an earlier thread on Java graph or chart library, where JFreeChart was found to be quite good, but, as stated in its FAQ, it's not meant for real-time rendering.
Can anyone recommend a comparable library that supports real-time rendering? Just some basic xy-rendering - for instance, getting a voltage signal from data acquisition system and plotting it as it comes (time on x-axis, voltage on y-axis).
What the FAQ actually says is that JFreeChart doesn't support hard real-time charting, meaning that the chart isn't updated when new data arrives or at deterministic interval after it. However I have found that JFreeChart can be used for the kind of applications you are describing. You can achieve 1 update per second, which is fine. I don't think a human eye can follow something quicker than this.
If you want something more than this, I doubt you will find anything in Java (or even in another language). Operating Systems that we use aren't designed to be real time. You can't have a guaranty that they will respond in a minimum interval after an event. A tight integration with the hardware driver will be needed to show more than 1-10 frames per second.
However, if you design your application correctly, the OS will do respond quickly and your application can easily display a "real-time" graph (meaning a graph that updates once a second). Just don't use your application to shut down a valve in an emergency situation!
http://www.live-graph.org/
Just stumbled upon a description on how to use the visualvm charting library. Looks very nice!
have a look at processing -- it's an open-source, java-based environment designed for all sorts of animated visualizations.
Well, if it has to be Java, then you might want to look into these.
Java Real-Time Systems (includes demo both real-time and non-real-timem, and JavaFX version of the charting application)
Real-time Java application development using multicore systems
Expedited Real-Time Task Graphs (This technology runs on Linux, but development can be done on any platform that supports Java 5.0 and Eclipse.)
JavaFX - A Pie Chart Demo
You probably have already found a good solution, but if not, I have recently done some work on a framework for producing 2D charts allowing for live updates at a rate of over 50 changes per second.
The original intention was to mimic the appearance of a chart recorder in a scrolling region of a web page, but I believe the approach has wider application.
A demo can be found at Chart Recorder Demo if anyone is interested.
The appearance is defined by a template (www.journeylog.co.uk/chart/templates/chartRecorder.xml). One feature is the ability to specify drawing either on the server or in the browser using ExplorerCanvas.
If anyone is interested I could start an open source project for it.
Fast enough for real time is swtchart, at least in my experience. Even with lots of data. Don't be scared away by the version number, yes it is a rather new API, but I use it successfully without problems.
As the name implies, it is based on SWT, which uses native OS drawing. Also it does some clever optimizations for drawing fast, like not drawing all points in the dataset (see Large Series Example Snippet).
this seems like a good candidate.
http://jchart2d.sourceforge.net/
demo:
http://jchart2d.sourceforge.net/applet.shtml
JCCkit is vary good library who are targetting less memory especially in embedded environment : https://sourceforge.net/projects/jcckit .
Takes less than <100 kb .
You could dig around the source for NetBeans. The profiler does real time graphing of various things such as memory usage.
SWT XYGraph can plot data with your own data provider, so you can create a real time data provider providing live data. With SWTChart and JFreeChart, you have to prepare the whole array for it.
This question has been answered well in:
Java Real time graph plotting
As VisualVM includes a Charting API, and this API is included in the JDK, you have a good/fast charting API available.