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
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
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
Just for the sake of argument. Both are http request (xhr), and its at least partially untrue it uses more server resources (depends totally on technology, will explain later). Short polling. Lot of request that are processed as they come on server. Creates a lot of traffic (uses resources, but frees them as soon as … Read more
SignalR provides ConnectionId for each connection. To find which connection belongs to whom (the user), we need to create a mapping between the connection and the user. This depends on how you identify a user in your application. In SignalR 2.0, this is done by using the inbuilt IPrincipal.Identity.Name, which is the logged in user … Read more
This worked for me: $cmd = “ping 127.0.0.1”; $descriptorspec = array( 0 => array(“pipe”, “r”), // stdin is a pipe that the child will read from 1 => array(“pipe”, “w”), // stdout is a pipe that the child will write to 2 => array(“pipe”, “w”) // stderr is a pipe that the child will write … 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