[open] Displaying in real time streamed data

Nilloc

Hi there!

I need to build an experiment up but I'm just starting to learn how to use Opensesame and how to code in Python, and I don't really know how to do it.. I hope some of you will be able to help me on this.

Here is what I would like to do :

First, I want to display streamed datas. To do so, I'd like to use them to rotating in real time around a 'z' axis a very basic shape such as a rectangle. Streamed datas will come from an Iphone sending them via an UDP protocol (I use an app called SensorData http://wavefrontlabs.com/Wavefront_Labs/Sensor_Data.html ). I found on their website this example of code but I'm not sure how to use it :

import SocketServer

PORTNO = 10552

class handler(SocketServer.DatagramRequestHandler):
    def handle(self):
        newmsg = self.rfile.readline().rstrip()
        print "Client %s said ``%s''" % (self.client_address[0], newmsg)
        self.wfile.write(self.server.oldmsg)
        self.server.oldmsg = newmsg

s = SocketServer.UDPServer(('',PORTNO), handler)
print "Awaiting UDP messages on port %d" % PORTNO
s.oldmsg = "This is the starting message."
s.serve_forever() 

That would be the first part of the experiment.

In a second time, I would like to combine / merge these streamed datas with some other datas already stored into a .csv file on my computer. Thus, will be displayed in real time a combination of datas coming from the Iphone and from the other .csv file.

It would be very helpful if you could give me some tips and advices about how to code this, i'm a bit lost!

Thank you for your time!

Nilloc

Edwin

Hi Nilloc,

It seems you already know how to get data from your device using a socket.

To load data from a csv, you could simply use Python's native open function, or NumPy's loadtxt. See below:

open

# path to the csv file
csvpath = "C:\Users\user\this\is\an\example.csv"

# open the csv file
csvfile = open(csvpath, 'r')

# read all the data (to a list, containing strings for each line in the csv)
alldata = csvfile.readlines()

# close csv again
csvfile.close()

# do your own data parsing here

loadtxt

import numpy

# path to the csv file
csvpath = "C:\Users\user\this\is\an\example.csv"

# load all the data
alldata = numpy.loadtxt(csvpath, dtype=float, unpack=True)

Presenting the data on the screen can be done by using the canvas functions.

Please note that this all requires you to know a bit of Python. If you're unfamiliar with it, please have a look at the page for tips on where to learn Python.

Good luck and happy holidays!

Edwin

Nilloc

Thank you very much Edwin,

I've learnt the basics and with your tips, I made the code I needed so far.
I think I might ask for your help later when it will get more complex !

Happy holidays and thank you again,

Nilloc