1. PYTHON EEG ANALYSIS EXAMPLE FROM THINK PYTHON HOW TO THINK LIKE A COMPUTER SCIENTIST

2. EEG DATA COLLECTION

3. THEIR TEST BENCH

4. GENERATES A CSV FILE LOOKS LIKE THE FOLLOWING IN EXCEL Channels sample number

5. LOOKING AT IT IN NOTEPAD++

6. Suppose we just want channel 2 and none of the other data. We will use Python to extract that column only. Once it is extracted we can graph it.

7. OPEN THE FILE AND READ IT. File=open("eegdata.csv",'r') File.readline(); # Get rid of the first line. # It contains only header data for line in File: print line # The above should open the file and print it out one line at a time. # As soon as this works we can then process each line

8. REMEMBER SPLIT? If we have a string (or line) that is a CSV string we can split it into pieces and place the result into a list. Example : str = “34,23,65,77,12” a = str.split(‘,’) print a ['34', '23', '65', '77', '12'] But these are strings in a list and not numbers. So. a[2] is ‘65’. Can we convert this guy to a float? float(a[2]) is now 65 Capice?!

9. THE SCRIPT File=open("eegdata.csv",'r') File.readline(); channel = [] for line in File: list=line.split(',') channel.append(float(list[2])) print channel plot (channel[0:128)) # only plot the first 128 samples

11. WHAT ABOUT MULTIPLE GRAPHS File=open("eegdata.csv",'r') File.readline(); channel = [] for line in File: list=line.split(',') channel.append(float(list[2])) print channel figure(1) plot(channel[:128]) figure(2) plot(channel[128:256])