Question

I am trying to read a column of data from a csv file and create a histogram for it. I could read the data into an array but was not able to make the histogram. Here is what I did:

thimar=csv.reader(open('thimar.csv', 'rb'))
thimar_list=[]
thimar_list.extend(thimar)
z=[]
for data in thimar_list:
    z.append(data[7])
zz=np.array(z)
n, bins, patches = plt.hist(zz, 50, normed=1)

which gives me the error:

TypeError: cannot perform reduce with flexible type

Any idea what is going on?

Answer 1

modify the sixth line to cast string to numeric

    z.append(float(data[7]))

with this i got some plot with my made up data.