Python: Reading CSV file and plotting a scatter

Question

I've written a script to compute large csv files in dimensions: 27000 rows x 22 column. How can I read in the CSV file in order to use it in matplotlib in a scattered plot like the one in this thread?

axis range in scatter graphs

The concept of generating a scatter plot is understood. Attempts have been made to parse csv file by e.g.:

data=csv.reader(open('some_file.csv, 'rb'), delimiter='|', quotechar='"')

but without success.

Answer 1

Here is a quick solution

def getColumn(filename, column):
    results = csv.reader(open(filename), delimiter="\t")
    return [result[column] for result in results]

and then you can use it like this

time = getColumn("filename",0)
volt = getColumn("filaname",1)

plt.figure("Time/Volt")
plt.xlabel("Time(ms)")
plt.ylabel("Volt(mV)")
plt.plot(time,volt)

Answer 2

Is that the correct delimiter? Did you read the documentation? http://docs.python.org/library/csv.html

data is a file-like object. you must iterate over it to access the data. each line is a list as marcus points out in his example.