平均负数python

Question

我需要文件中3个向量的平均值。这是文件：

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

如您所见，第二列仅包含负数。当我尝试使用代码进行平均时：

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

我得到一个正数！

numpy.mean有什么用吗？

Answer 1

我测试了它，代码按预期工作。确保vec在开始时为空。