Instead of polling, you can use server-sent-events, which does not put as much strain on the server as data is only sent if a new event has happened (like a new row). More can be found out about them here: https://developer.mozilla.org/en-US/docs/Web/API/Server-sent_events/Using_server-sent_events Here is an example, as the one in the link is not that good. … Read more
Here’s the working version of the code in question (requires at least version Matplotlib 1.1.0 from 2011-11-14): import numpy as np import matplotlib.pyplot as plt plt.axis([0, 10, 0, 1]) for i in range(10): y = np.random.random() plt.scatter(i, y) plt.pause(0.05) plt.show() Note the call to plt.pause(0.05), which both draws the new data and runs the GUI’s … Read more
If you want to keep the file as a persistent store of your data to prevent a loss of stream in case of a system crash or one of the members in your network of running processes dies, you can still continue on writing to a file and reading from it. If you do not … Read more
Update (March 2012): Oracle appears to have quietly disassembled their JavaRTS development team. There isn’t a good answer to this question. There certainly isn’t enough critical mass to say there’s a current most-popular RT JVM. US Defense systems I’m aware of use JavaRTS, IBM’s WebSphere RT, and PERC. Aviation platforms use aicas JamaicaVM. Most of … Read more
I am an avionics software engineer. I was able to participate in several development projects. The languages I used in those projects are: C, C++, and Real-time Java. C is great. C++ is not so bad but C/C++ require strict coding standards for the safety considerations such as DO-178B. I think Real-time Java is the … Read more
As Edric mentioned, you’ll definitely want to include a drawnow command after the call to plot to force an update of the graphics. However, there is a much more efficient and smoother method to animate plots that doesn’t involve recreating the entire plot each time. You can simply initialize your plot, capture a handle to … Read more
I do not know if this can help you but I’ll tell you where I am for real-time update page feed: (permissions : manage_page,offline_access,read_stream) your application must be linked to the page (then install the application but not required to have a tab ex. create tab https://graph.facebook.com/PAGE_ID/tabs?app_id=APP_ID&method=POST&access_token=PAGE_ACCESS_TOKEN and delete tab TAB_ID=PAGE_ID.’/tabs/app_’.APP_ID; https://graph.facebook.com/TAB_ID?method=DELETE&access_token=PAGE_ACCESS_TOKEN) function page_access_token($page_id,$access_token){ $page_token_url=”https://graph.facebook.com/” … Read more
You need to use the NTP (Network Time Protocol) protocol: Here is some code I found somewhere else… and I am using it. This uses the Apache Commons library, which can be installed using Gradle (adding a dependency on commons-net:commons-net:3.6) If you need a list of time servers, check: http://tf.nist.gov/service/time-servers.html Here is some Java Code … Read more
Curiously, your code works perfectly fine on my quad core under Win7, generating values exactly 2 ms apart almost every time. So I’ve done a more thorough test. Here’s my example output for Thread.Sleep(1). The code prints the number of ms between consecutive calls to DateTime.UtcNow in a loop: Each row contains 100 characters, and … Read more
So, to begin with, I put my project on github, if you want access to the full code: https://github.com/jdutheil/nodePHP It is a very simple example project: a web chat. You just have an author and message, and when you press send it is saved in a mysql database. The idea is to send real time … Read more