平均负数python

Question

I need the average of 3 vectors in a file. This is the file:

7.308017466911098700e-01 -5.497365223199360800e-01 -1.324069582379517300e-01
7.142889846599955700e-01 -5.300077858149733200e-01 -1.214793135300424200e-01
7.142889846599955700e-01 -5.300077858149733200e-01 -1.214793135300424200e-01
7.142889846599955700e-01 -5.300077858149733200e-01 -1.214793135300424200e-01
6.835045107440532700e-01 -4.980522174917749700e-01 -1.158373119954510000e-01
6.835045107440532700e-01 -4.980522174917749700e-01 -1.158373119954510000e-01
6.835045107440532700e-01 -4.980522174917749700e-01 -1.158373119954510000e-01
6.835045107440532700e-01 -4.980522174917749700e-01 -1.158373119954510000e-01
7.440304087049756100e-01 -5.568396579851897500e-01 -1.014631831749943100e-01
7.021751417881535500e-01 -6.350121671924353600e-01 -5.052342816781073300e-02

As you can see the second column contains only negative numbers. When I try to average with the code:

with open(myfile) as fin:
    for line in fin:
        vec.append(float(line.split()[1]))
    mean1=np.mean(vec)
    print mean1

I get a positive number!

Is there something with numpy.mean?

Answer 1

I've tested it, and the code works as expected. Make sure vec is empty at the start.